EE vs O2 vs Three vs Vodafone: Business Mobile Plans

BT has always owned EE, and nothing about that has changed. O2 is now owned by Virgin Media O2, a joint venture between Telefonica and Liberty Global, and since August 2025, most of O2's direct business sales have run through O2 Daisy, a company jointly owned by Virgin Media O2 and Daisy Group. We cover what that means for you in more detail below.

The other structural shift is Vodafone and Three. The two completed their UK merger in June 2025 to form VodafoneThree, and by May 2026, the company had finished combining the two networks' core and radio access infrastructure using a technology called Multi-Operator Core Network sharing. In practice, that means a Vodafone customer's phone can now connect to a Three mast, and vice versa, whichever gives the stronger signal at that moment.

Vodafone and Three are no longer separate networks from a coverage standpoint, even though they're still sold as separate SIMs with separate pricing and separate customer service teams. Opensignal's independent testing, run over the final quarter of 2025, still reports Vodafone and Three's real-world performance separately because the network sharing rollout was still in progress and users were still seeing measurably different experiences on each brand. That gap is closing, but it hasn't closed yet, so it's still worth comparing Vodafone and Three on their own merits.

That leaves EE (BT-owned), O2 (sold to SMEs via O2 Daisy) and VodafoneThree (selling under two customer-facing brands) as the three pieces of infrastructure that everything else in this guide, and every reseller on the market, is supported by.

What Is EE Best For?

EE is best for businesses that see coverage and speed as non-negotiable, and are prepared to pay a premium for that reliability. It's the network to choose if your team works in places where a dropped call or a stalled upload costs you time or money.

Key Features of EE Business

• Business Essential SIM-only plans from £13/month (1GB) up to £25/month for unlimited data, all on 24-month terms, with 12-month and 30-day options also available

• Business All Rounder plans add Inclusive Extras, swappable every 30 days between perks like Apple Music, Microsoft 365 Personal or 500 minutes to call Europe, from £20/month for 10GB

• Stay Connected Data throttles you to 0.5Mbps rather than cutting you off once you use your monthly allowance, useful for field staff who need maps and messaging even after their data runs out

• Free access to more than 160,000 BT WiFi hubs across the UK through WiFi Coverage Boost, on top of the mobile network itself

• Ranked the UK's best network for 13 years running by RootMetrics, and the outright winner of Opensignal's Reliability, Consistent Quality, Download Speed, Upload Speed, Video, Games and 5G Coverage Experience awards in its January 2026 report

• 5G Roam Abroad Pass covers 47 European destinations, and eSIM support lets you onboard new starters remotely within minutes

Trade-Offs to Consider

• The most expensive of the four networks at almost every tier, particularly once you move past the entry-level Essential plans

• EU roaming isn't free: it costs £2.38 a day for anyone who joined or upgraded after October 2021, which adds up quickly for teams that travel regularly

• The annual price rise applies to every plan, every year, for the life of your contract, at £2.08 a month for SIM-only plans and £3 for handset plans

• O2 still edges out EE on Opensignal's overall Coverage Experience award, even though EE wins outright on 5G coverage specifically

EE works well if your business can't tolerate patchy signal, particularly for staff working indoors in older buildings, on building sites, or moving between locations during the day. It's a weaker fit if your priority is keeping the monthly bill as low as possible.

If your business is also weighing up fixed connectivity, our BT vs EE broadband comparison looks at how EE's mobile network stacks up as a fixed-line alternative.

What Is O2 Best For?

O2 is worth considering if you want a straightforward, moderately priced SIM with free European roaming built in from the start, rather than paying extra for it as an add-on.

Key Features of O2 Business

• SIM-only plans from around £11 a month, with data allowances from 1GB up to unlimited and a choice of 12 or 24-month terms

• EU roaming included at no extra charge for usage up to 25GB, which covers most business trips without needing a separate roaming pass

• O2 Priority gives staff early access to gig and event tickets, and O2 WiFi provides free hotspot access around the UK

• The lowest annual price rise of the four networks at £1.50 a month, applied each 1 April

• Business apps and add-ons can be attached from the start of the contract or added later on their own rolling 30-day terms

Trade-Offs to Consider

• O2 comes fourth of the four networks on Opensignal's independent download and upload speed testing, at 32.8Mbps and 6.4Mbps respectively

• Most small business accounts are sold and serviced through O2 Daisy rather than Telefónica directly, which is worth understanding before you sign (see below)

• Ofcom's most recent quarterly complaints data put O2 among the higher complaint rates for pay-monthly mobile services, driven partly by fallout from mid-contract price rise announcements

• 5G coverage lags behind EE and VodafoneThree in Opensignal's testing, even though O2 wins outright on overall Coverage Experience

O2 is a sensible middle-ground choice for businesses that want predictable pricing, free EU roaming as standard, and don't need the fastest possible speeds. It's a weaker fit if raw download performance drives productivity for your team, say for large file transfers or video work done on the move.

What Is O2 Daisy?

If you've bought an O2 business SIM recently, or you're comparing quotes now, you may have noticed the paperwork comes from O2 Daisy rather than O2 or Telefonica directly. This isn't a separate network or a downgrade: it's the result of a restructuring.

In May 2025, Virgin Media O2 and Daisy Group agreed to combine their business-to-business operations into a single company. That company, O2 Daisy, launched in August 2025, with Virgin Media O2 holding 70% and Daisy Group 30%. It now serves the full range of O2's business customers, from sole traders and small offices up to large enterprise and public sector accounts, combining O2's mobile network with Daisy's broader IT and communications products.

For most small businesses, what this means in practice is that you're still using O2's network and O2's coverage, but your contract, billing and customer service are more likely to run through Daisy Communications Ltd, which is separately regulated by the FCA for consumer credit. It's worth knowing this so you're not caught off guard by the branding on your bill, but it doesn't change the network performance you'll actually get.

What Is Three Best For?

Three has historically been the budget option of the big four, and that's still largely true, but the VodafoneThree merger has changed what you're actually getting for that lower price.

Key Features of Three Business

• SIM-only plans start from £9 a month for 3GB, rising through 25GB, 80GB and unlimited tiers, all with unlimited UK calls and texts

• Wins outright on Opensignal's 5G Download Speed and 5G Upload Speed awards, at 187Mbps and 20.2Mbps respectively, comfortably ahead of the other three networks

• 24-month Boundless plans can include Go Roam in Europe as standard, covering 49 European destinations without the £2 daily roaming charge that applies to standard plans

• Three Business Adapt handles teams of 50 or more with bill analytics and dedicated support, while smaller teams can multibuy SIMs for a discount

• Now benefits from VodafoneThree's combined mast footprint, closing many of the coverage gaps that used to be Three's biggest weakness

Trade-Offs to Consider

• Roaming isn't free by default: standard plans charge £2 a day in Europe, £5 a day for Go Roam Around the World destinations, and £7 a day for the Go Roam Around the World Extra tier

• Three Business's own Trustpilot page, which is separate from Three's much larger consumer profile, shows a considerably lower score, reflecting a smaller but more mixed set of reviews (see below)

• Opensignal's testing still ranks Three fourth for overall download speed at a national level, even though it leads specifically on 5G

• Coverage historically lagged EE, O2 and Vodafone in rural areas, and while VodafoneThree's mast-sharing is closing that gap, the rollout is still in progress in some regions

Three is worth considering if your business is comfortable managing roaming as an add-on rather than wanting it bundled in, and if keeping the monthly SIM cost down matters more than winning every network benchmark. It's a stronger choice today than it was before the merger, since your signal now effectively benefits from Vodafone's mast network as well.

What Is Vodafone Best For?

Vodafone suits businesses that want the broadest combined coverage available in the UK, free European roaming without needing to pay for a separate business tier, and a network that's actively being expanded rather than standing still.

Key Features of Vodafone Business

• SIM-only plans from £13.33 a month for 1GB, through to Unlimited Premier at £40 a month with a 2x speed boost and roaming across 84 worldwide destinations

• Small Business Traveller lets accounts with fewer than 10 connections use their UK minutes, texts and data for free across Vodafone's Europe Zone, with World Zone access available for £5 a day

• Vodafone customers can now automatically use Three's network for additional coverage at no extra cost, a direct result of the VodafoneThree merger

• Multibuy SIM deals discount each additional connection when you buy five to nine SIMs together on a 24-month unlimited plan

• Inclusive Secure Net on higher-tier plans helps protect against viruses, malware and phishing when browsing or using email on a business device

Trade-Offs to Consider

• Standard plan pricing sits above O2 and Three at most data tiers, particularly once you move beyond the heavily discounted promotional prices shown on the website

• The annual price rise varies by plan type, from £2.09 a month on multibuy small business SIMs to £2.50 a month on general pay-monthly plans, on top of out-of-bundle charges rising by CPI plus 3.9%

• Opensignal's testing places Vodafone third of the four networks on both overall and 5G download speed, behind EE and Three

• Businesses with 10 or more employees don't qualify for the free Small Business Traveller roaming and need to look at Business Premier plans instead

Vodafone is a strong fit for multi-site businesses, international traders, or any company where a wider combined coverage footprint matters more than shaving a few pounds off the monthly SIM cost.

If you're also comparing fixed connectivity, our BT vs Virgin Media broadband comparison and business broadband hub cover the wired side of the same decision.

EE vs O2 vs Three vs Vodafone: Pricing Compared

Comparing headline prices across four networks is harder than it looks, because each provider structures its data tiers, discounts and promotions differently. The table below uses representative 24-month SIM-only pricing, excluding VAT, as of August 2026.

Three's £5 monthly recurring payment discount, and Vodafone's frequent promotional pricing mean the advertised price and the price you actually pay once a promotion ends can differ noticeably. It's worth checking the "increasing to" figures shown at checkout on any provider's site rather than only looking at the headline monthly cost.

Annual Price Rises

All four networks raise prices annually during your minimum term, and the mechanism differs enough between them that it's worth checking before you sign rather than after your first increased bill arrives.

• EE adds £2.08 a month (ex VAT) to SIM-only and data SIM plans, and £3 a month to handset plans, every 31 March, with out-of-bundle charges rising by 5%

• O2 adds £1.50 a month (ex VAT) to airtime plans every 1 April, the smallest fixed increase of the four

• Three scales the increase to your plan price: £0.50 a month if your original charge was £9.99 or less, £0.75 a month for plans between £10 and £20, and £1.50 a month above £20.01, applied each April. Three Business Adapt and Dynamic plans instead rise by 4.5% each year

• Vodafone adds £2.09 a month on small business multibuy SIM plans, or £2.50 a month on general pay-monthly SIM plans, each 1 April, with out-of-bundle charges rising by CPI plus 3.9%

None of these increases are optional or negotiable mid-contract, and they apply whether or not you're within your minimum term. Building the rise into your budgeting from day one avoids an unwelcome surprise a year in.

Pooled and Shared Data Explained

If you're managing more than a handful of connections, a pooled or shared data plan can be considerably more efficient than giving everyone an identical individual allowance. Instead of one person running out of data mid-month while another barely touches theirs, a shared pool lets the whole team draw from a single monthly allowance.

EE offers this through its Shared Plan for businesses of 10 to 50 employees, Vodafone offers OneNumber and shared allowance options on its larger business plans, and O2 and Three both support data flexing that lets you adjust individual allowances up or down, typically once every 30 days, without renegotiating the whole contract. In our experience, pooled data works best for businesses with uneven usage across the team, such as a mix of desk-based staff and field engineers, and works less well if everyone's usage pattern looks broadly similar, in which case individual allowances are simpler to manage and audit.

Which Network Has the Best Coverage?

Coverage in the UK isn't uniform, and the gap between networks is often much wider in specific regions than the national averages suggest. Ofcom's Connected Nations 2025 report found that 4G geographic coverage from all four operators combined reaches around 90% of England's landmass, while Scotland remains the UK nation with the lowest levels of 4G geographic coverage of the four nations, despite steady improvement year on year.

Opensignal's regional testing, based on real user data collected between October and December 2025, gives a more granular, operator-specific picture. Across most English regions, including the East Midlands, Eastern England, London, the North East, the North West, the South East, the South West and the West Midlands, EE and Three lead on download speed, while O2's advantage is concentrated in coverage consistency rather than raw speed. In Wales and the North West specifically, Three's average download speed pulls ahead of the other three networks by a wide margin, a direct benefit of the combined VodafoneThree spectrum.

Northern Ireland stands out as the region where all four networks perform most closely together, and where O2's 5G availability, at 73% of the time in Opensignal's data, actually leads EE's. This is worth knowing if your business operates across the UK and Ireland, since it's one of the few regions where the usual "EE wins on everything" pattern doesn't hold.

5G Rollout Across the UK

Ofcom's 2025 report found that 5G standalone, the newer, faster generation of 5G that doesn't rely on a 4G connection, was available to around 83% of the UK population at a high confidence level, up sharply from the previous year. Virgin Media O2 has framed 5G standalone as central to its strategy and reported its standalone network live across hundreds of towns and reaching around 70% of the UK population by September 2025.

EE, which markets its standalone network as 5G+, was reaching around half the UK population by mid-2025 with further expansion planned. VodafoneThree has set a public target of reaching around 90% of the UK population with 5G standalone within three years of the network integration completing.

In practical terms, this means the gap between "has 5G" and "has the newer, faster kind of 5G" is still closing, and which network gets there first in your specific area will keep shifting through 2026 and 2027. If 5G speed matters to your business, for example for on-site video streaming or large file uploads, it's worth checking current coverage at your postcode rather than relying on national percentages.

What to Do If You Experience Poor Coverage

If you've signed up and coverage turns out to be worse than expected at a specific site, you have a few practical options before assuming you're stuck.

• Check the network's own coverage map for your exact postcode, not just the general area, since signal can vary considerably between adjacent streets depending on terrain and building density

• Ask about a femtocell or signal booster for a specific building, which some business providers can supply for persistent indoor dead spots

• Consider a dual-network SIM or eSIM if a critical location has inconsistent coverage from your main provider, since eSIM makes it straightforward to run a second network's SIM profile alongside your primary one

• Use your provider's minimum service commitments where they exist. Most business contracts include a right to leave without penalty if the network can't fix a coverage issue at your registered address within a set period, so it's worth checking your specific terms

• Fall back to WiFi calling where your device and provider support it, since this routes calls over your office or home broadband rather than the mobile network entirely

Plans and Contract Lengths Compared

Contract flexibility varies more than most businesses expect, and the right length depends heavily on how settled your headcount and requirements are.

• EE offers 30-day, 12-month and 24-month terms, with Upgrade Anytime available on higher-tier plans for accounts under 50 connections that meet eligibility conditions

• O2 offers 12 and 24-month terms as standard, with data allowances flexible on a rolling monthly basis even within a fixed contract length

• Three is the most flexible of the four on paper, offering 1, 12 and 24-month terms across its full SIM range, making it a reasonable option for short-term or seasonal needs

• Vodafone offers 30-day, 12-month and 24-month terms, with 24-month plans generally carrying the lowest headline price and the best promotional discounts

As a general rule, 24-month contracts offer the lowest monthly price but the least flexibility; 12-month contracts sit in the middle, and 30-day or 1-month rolling plans cost more per month but let you scale headcount up or down without penalty. In our experience, businesses with a stable, predictable team size do best on 24-month deals, while businesses that expect to hire, contract or restructure within the next year often find the extra flexibility of a shorter term worth the higher monthly cost.

Customer Service and Complaints

Independent review scores for these four networks vary wildly depending on which page you look at, and it's worth understanding why before drawing conclusions from a single star rating.

On Trustpilot, the general consumer pages for these brands score considerably higher than their business-specific pages: Vodafone's main UK profile sits around 4.7 out of 5 from roughly 139,000 reviews, EE's around 4.3 from over 107,000, and Three's around 4.6 from more than 66,000. O2's general profile is the exception, sitting at a considerably lower 2.6 out of 5.

Business-specific Trustpilot pages tell a different story: EE Business sits around 3.4 out of 5 from a much smaller sample of 289 reviews, Three Business around 2.5 from 94 reviews, and the O2 Business Shop, operated by Daisy, around 1.3 from 74 reviews. These smaller samples are more volatile and shouldn't be read with the same confidence as the larger consumer figures, but the consistent pattern of business-specific pages scoring lower than general consumer ones is worth noting rather than dismissing.

Ofcom's regulator-audited complaints data gives a steadier picture, since it's based on actual complaints referred to the regulator rather than voluntary reviews. In its most recent quarterly report, Ofcom found EE, Giffgaff and Vodafone generated the fewest pay-monthly mobile complaints at one per 100,000 customers, O2 sat at three per 100,000, and Three matched the industry average at two per 100,000. The previous quarter's spike in O2 complaints was largely tied to backlash over mid-contract price rise announcements, a pattern that affected the whole industry rather than being unique to O2.

Taken together, we'd weight Ofcom's complaints data more heavily than any single Trustpilot score when comparing these four networks, since it covers a consistent, much larger sample and isn't affected by how enthusiastically each brand solicits reviews from happy customers.

Best Business Mobile Networks By Use Case

Rather than picking one overall winner, it's usually more useful to match the network to what your business actually needs.

• Field sales/support teams and trades that need reliable coverage in awkward indoor locations, building sites or rural areas are generally best served by EE, given its lead on Opensignal's coverage and reliability metrics

• Businesses that travel to Europe get the most value from O2's free 25GB EU roaming allowance or Vodafone's free Small Business Traveller for accounts under 10 employees, since both avoid daily roaming charges entirely

• Cost-conscious small teams tend to do best on Three, particularly if data needs are modest and international roaming isn't a frequent requirement

• Multi-site businesses benefit most from Vodafone's combined VodafoneThree coverage footprint, now the widest in the UK by mast count

• Large fleets of 50 or more connections are worth negotiating bespoke terms for directly with any of the four providers, since published SIM-only pricing rarely reflects what's actually achievable at scale

When to Look at Alternatives

None of the big four is the right answer for every business, and it's worth considering an alternative in a few specific situations.

• You need coverage in a specific remote or rural location where none of the big four performs well, in which case checking Ofcom's postcode-level coverage checker before committing is more useful than any national ranking

• You want a single provider for mobile, broadband and a hosted phone system, in which case a bundled deal or a specialist unified communications provider may work out cheaper than three separate contracts

• Your business needs 50 or more connections with detailed bill analytics and account management, in which case Three Business Adapt or a dedicated enterprise account with any of the four is worth exploring directly rather than through a standard SIM-only shop

• You'd rather deal with a smaller, UK-based reseller than a corporate call centre, in which case an MVNO running on one of the big three networks is worth a look (see below)

Business Mobile Plans for Startups and Sole Traders

If you're setting up a new business, it's tempting to reach for the cheapest SIM-only deal available, but a few things are worth checking specifically for startups. First, confirm whether the plan you're looking at is a business tariff or a consumer SIM being sold to you informally, since business tariffs usually include VAT-exclusive pricing, itemised billing suitable for expenses, and access to a business account portal that consumer SIMs don't offer. Second, if you're not yet VAT registered, remember that the ex-VAT prices quoted throughout this guide will cost 20% more on your actual bill. Third, rolling 30-day or 12-month contracts are usually worth the modest premium over 24-month deals in a startup's first year, since you don't yet know how many connections you'll need in 12 months.

EU and International Roaming Compared

Roaming policy is one of the areas where these four networks differ most, and it's worth checking carefully if your team travels for work.

O2 and Vodafone are the two strongest options if EU travel is routine for your business, since both build free roaming into standard small business plans rather than charging a daily fee. EE and Three both treat EU roaming as a paid extra by default, though both offer ways to bundle it in for a lower effective cost if you commit to the right plan upfront.

Contract Flexibility

Beyond the headline contract length, it's worth understanding what happens if your business needs change mid-term. Early termination charges typically apply across all four networks if you cancel before your minimum term ends, usually calculated as the remaining months' charges, sometimes discounted for early settlement. Upgrading mid-contract is generally easier than leaving: EE's Upgrade Anytime, O2's flexible tariff changes, Three's plan swaps and Vodafone's Xtra Plans all let you move to a different tier without necessarily resetting your minimum term, though the exact rules vary.

Multi-line discounts are worth asking about even if they're not prominently advertised. EE offers Smart Benefit discounts from two lines upward, Vodafone discounts multibuy SIMs bought five to nine at a time, and Three and O2 both offer negotiated rates for larger connection counts. In our experience, the advertised per-SIM price on any of these networks is rarely the final price once you're negotiating for more than five or six connections, so it's worth asking directly rather than assuming the website price is fixed.

Managing Multiple SIMs and eSIMs

Once your business has more than a handful of connections, managing physical SIMs becomes its own administrative task. All four networks now support eSIM, which lets you activate a new connection remotely by sending a QR code or activation link rather than posting a physical card, a time-saver when onboarding remote staff or replacing a lost device quickly. EE, O2, Three and Vodafone all offer online account portals that let a nominated administrator add or remove connections, set individual or shared spend caps, and see usage across the whole team without calling customer service for every change. If you're managing a fleet of connected devices rather than staff phones, such as tablets, payment terminals or IoT sensors, it's worth asking specifically about data-only SIMs and device management tools, since the consumer-facing SIM-only pages on most providers' websites aren't designed with that use case in mind.

Smaller Business Mobile Providers

The big four aren't the only option, and a smaller provider running on the same networks can sometimes offer better value or a more responsive service for a small business.

Gamma Mobile is a channel-only business MVNO, meaning it's sold through telecoms resellers rather than direct to businesses, running on the VodafoneThree network. It typically costs from around £10 a month per SIM and is a sensible option if you already work with a Gamma reseller for fixed-line or unified communications services and want to consolidate billing.

IQ Mobile runs on the EE network and offers business SIM-only plans from around £7 a month, with pooled data, a management portal, and no fixed 24-month lock-in as standard. It's worth a look if you want EE's coverage without EE's own list price, though it's a smaller company with a less established business track record than the big four.

Plan.com offers bespoke business mobile services built on O2's network, managed through its own My.Plan portal, and is one of several O2 resellers worth comparing against O2 Daisy's own direct pricing.

Smaller providers like these can undercut the big four on price precisely because they're leasing network capacity wholesale rather than owning the infrastructure. The trade-off is usually a smaller support team and less negotiating leverage if something goes wrong, so it's worth weighing the savings against the level of account management your business actually needs.

Bundling Mobile with Broadband, a Leased Line or VoIP

If your business already buys broadband, a phone system or a leased line, it's worth checking whether bundling mobile in with the same provider saves money or simply adds complexity. BT bundles EE mobile alongside its business broadband, Virgin Media O2 offers combined mobile and broadband discounts under its Volt proposition, and Vodafone and Three, now sharing a parent company, are likely to push more combined fixed-and-mobile offers as VodafoneThree's integration continues.

The case for bundling is strongest if your business wants one bill and one support number for connectivity, and weakest if the best mobile deal and the best broadband deal happen to come from different providers, since a bundle discount rarely outweighs choosing the strongest option in each category separately.

Our guide to comparing SME phone and broadband bundles looks at this trade-off in more depth, and if resilience matters more to your business than saving a few pounds, our business broadband vs leased lines guide explains when a dedicated line is worth the extra cost over standard mobile or fixed broadband.

The PSTN Switch-Off

Separately from your mobile contract, it's worth knowing that Openreach is retiring the UK's old analogue phone network, known as PSTN, on 31 January 2027, with no further delay expected. This affects traditional landlines, alarm systems, lift lines and card payment terminals that still run over copper phone lines, not your mobile contract directly, but it's pushing many businesses toward VoIP-based phone systems at the same time as they're reviewing mobile contracts. If your business still relies on analogue lines for anything beyond a desk phone, it's worth auditing what's affected now rather than close to the deadline.

Our guides to VoIP systems and cloud phone systems cover what to move to before the switch-off.

Handsets vs SIM-Only

If your team already has devices, whether company-owned or under a bring-your-own-device policy, SIM-only is almost always the cheaper route, and every comparison in this guide has focused on SIM-only pricing for that reason. Handset contracts make more sense when you need to standardise devices across a team, want predictable device refresh cycles, or don't want the upfront cost of buying phones outright.

All four networks offer trade-in schemes that reduce the monthly cost of a new handset contract in exchange for your old device, and EE's Upgrade Anytime, O2's Switch Up, and equivalent schemes on Three and Vodafone let you refresh devices before the contract naturally ends, usually at 11 to 12 months into a longer agreement. In our experience, a mixed approach often works best for growing businesses: SIM-only for staff who supply their own devices, and handset contracts reserved for roles where the business needs to control the device, such as field staff using ruggedised phones or roles requiring specific security configurations.

Switching Business Mobile Providers

Switching provider is more straightforward than it used to be, though the process differs slightly depending on whether you're moving a single SIM or a whole fleet. For a small number of connections, you can typically order the new SIMs, port your numbers across, and cancel the old contract once the new service is live, with minimal downtime if you time the switch to your existing minimum term. For larger fleets, most providers offer a dedicated onboarding team to manage a phased migration, since moving 50 or more numbers on the same day carries more risk of disruption.

Before switching, check your current provider's early termination charges if you're still within a minimum term, confirm your new provider's coverage at every location your team actually works from rather than relying on national coverage maps, and agree an overlap period where both SIMs are briefly active so nobody loses signal mid-transfer.

Porting Your Business Number

Keeping your existing number when you switch is a legal right under Ofcom's rules, and the process itself is quick. Text "PAC" to 65075 from the phone whose number you want to keep, and your current provider must send you a Porting Authorisation Code within one working day, valid for 30 days. Give this code to your new provider, who will typically complete the port within one working day of receiving it.

For multiple numbers on a business account, most providers offer a bulk porting process managed by your account team rather than requiring each SIM to be ported individually. It's worth timing your final PAC request for a day when your team can tolerate a short window without service, since even a same-day port can involve an hour or two of downtime as the number transfers between networks.

Indoor and Outdoor Coverage

National coverage percentages, whether from Ofcom or an individual network's own coverage checker, are almost always based on outdoor signal strength. Indoor coverage, which is what actually matters for most office-based businesses, tells a noticeably different story. Ofcom's data shows indoor 4G coverage in rural England ranging from 77% to 85% depending on the operator, compared with 97% to 99% in urban areas, a gap that widens further once you factor in older buildings, basements, and steel or concrete construction that blocks signal regardless of how strong outdoor coverage is nearby.

Opensignal's Time on Network and Coverage Experience metrics are more useful here, since they're built from real user measurements taken mostly indoors, reflecting where people actually spend their working day rather than a theoretical outdoor signal map. If your business operates from an older building, a basement office, or a site with unusual construction, it's worth testing actual indoor signal with a SIM from your shortlisted provider before committing to a contract, rather than trusting a national coverage percentage that was never measuring your specific situation in the first place.

Getting the Best Value on a Business Mobile Contract

A few practical habits make the difference between overpaying and getting a competitive deal, regardless of which network you choose.

• Compare like-for-like data allowances rather than headline prices, since a plan that looks cheaper on the front page can work out more expensive once you account for a smaller data allowance or a shorter promotional period

• Ask about multi-line and negotiated pricing once you have more than five connections, since published SIM-only rates rarely reflect what's achievable at scale

• Factor in the annual price rise for the full contract term, not just the first year's cost, particularly on 24-month deals where the increase compounds

• Check whether your team actually needs unlimited data, since a well-sized allowance with rollover or flex options is often cheaper than paying for unlimited data nobody's close to using

• Review your contract 60 to 90 days before renewal, since this is typically your strongest negotiating window, and providers are more likely to offer their best retention pricing shortly before you're free to leave

FAQs on Business Mobile Plans

Which business mobile network is cheapest?

Three. It's is generally the cheapest entry point, with SIM-only plans starting from £9 a month, though O2 is competitive at the low end too. The cheapest headline price isn't always the cheapest overall cost once roaming, annual price rises and data allowances are factored in.

Which business mobile network has the best coverage?

O2. It wins outright on Opensignal's overall Coverage Experience metric, while EE leads specifically on 5G coverage. Coverage varies significantly by region and by indoor versus outdoor use, so it's worth checking a postcode-level coverage map rather than relying on either headline claim alone.

Are Vodafone and Three the same network now?

No, but increasingly so. Vodafone and Three merged into VodafoneThree in June 2025 and completed shared core and radio network integration by May 2026, meaning customers on either brand can now connect to the stronger of the two networks' masts.

They still operate as separate brands with separate pricing, contracts and customer service.

What is O2 Daisy?

O2 Daisy is a joint venture between Virgin Media O2 and Daisy Group, launched in August 2025, that now handles most of O2's direct business sales and support. It uses O2's mobile network, but your contract and billing are likely to run through Daisy Communications Ltd.

Which business mobile network is fastest?

EE. It leads on overall download and upload speed in Opensignal's most recent testing, at 53.2Mbps and 10.4Mbps respectively. Three leads specifically on 5G speed, reaching 187Mbps for download when connected to a 5G signal.

Do UK mobile networks charge for EU roaming?

O2 includes free EU roaming up to 25GB as standard, and Vodafone offers it free for small business accounts under 10 employees. EE and Three both charge a daily roaming fee by default, though both offer ways to bundle inclusive roaming into a higher-tier plan.

Can I keep my number when switching business mobile providers?

Yes. Text "PAC" to 65075 to request a porting code from your current provider, which must arrive within one working day and stays valid for 30 days. Your new provider can then complete the port, usually within one working day of receiving the code.

How much do business mobile prices rise each year?

EE, O2, Three and Vodafone all apply an annual increase during your contract's minimum term. EE adds £2.08 a month to SIM-only plans, O2 adds £1.50, Three adds between £0.50 and £1.50 depending on your plan price, and Vodafone adds £2.09 to £2.50 depending on the plan type, all applied each spring.

Is it worth using a smaller reseller for a business mobile plan?

It can be, particularly for cost-conscious small businesses. Providers like Gamma Mobile and IQ Mobile run on the same networks as the big four but often undercut their list prices, in exchange for a smaller support team and less scope for bespoke negotiation.

Our Verdict: Choosing a Business Mobile Network

If coverage and speed are what matter most to your business, particularly for field staff working indoors or in awkward locations, EE remains the strongest choice, even at a premium over the other three. If you travel to Europe regularly and want that covered without a daily charge, O2's free 25GB roaming or Vodafone's free Small Business Traveller for small accounts both solve that problem directly.

If keeping costs down is the priority and your team's data needs are modest, Three is worth a serious look now that it benefits from VodafoneThree's expanded coverage, something that wasn't true even eighteen months ago. And if your business operates across multiple sites or needs the widest possible combined footprint, Vodafone's position within VodafoneThree makes it the network most likely to keep expanding its coverage advantage through the rest of this decade.

None of these four is automatically right for every business. A single-site office with reliable WiFi might do perfectly well on Three's cheapest plan, while a field services business with staff working in rural areas may find EE's premium justified within the first month of avoiding dropped calls. It's worth checking live pricing and coverage at your specific postcodes before committing, since terms, promotions and network coverage all continue to shift as the VodafoneThree integration and O2 Daisy restructuring both continue through 2026 and beyond.