Business Data SIMs & Mobile Broadband: A Buyer's Guide (2026)

Not every business SIM goes in a phone. Data-only SIMs and mobile broadband quietly power a growing share of business connectivity in 2026 - tablets and laptops on the road, routers keeping a site online, 5G as a primary or backup connection, and a long tail of IoT devices from payment terminals to vehicle trackers. These connections are often bought ad hoc, one device at a time, with nobody checking whether they are on the right plan or pooled with the rest of the estate - which is exactly how they become a source of quiet overspend. As the person who signs off our connectivity bills, I treat data SIMs as part of the mobile estate, not a separate afterthought. This buyer's guide explains the options, what they cost, and how to buy them well. If you want your data SIMs priced alongside your handsets, get a business mobile quote and we will compare the lot across EE, Vodafone and O2.

What is a business data SIM?

A data-only SIM does exactly one thing: it provides mobile data, with no voice calls or text messaging. It is the right product for any device that needs to be online but is not a phone:

• Tablets and laptops used by staff on the road or between sites.
• Mobile broadband routers and MiFi units that share a connection with multiple devices over Wi-Fi.
• IoT and machine-to-machine devices - payment terminals, vehicle trackers, sensors, digital signage, alarm and CCTV systems.
• Backup and failover for a premises whose main internet is fixed-line.

The "business" part matters for the same reasons it does on a phone SIM: consolidated VAT billing, the ability to pool data with the rest of the estate, account management and spend controls. A consumer data SIM works in the device, but the business loses the pooling and control that make a multi-device estate manageable.

Mobile broadband: 4G/5G routers and MiFi

Mobile broadband means using the mobile network for internet rather than a fixed line, through one of two device types:

• MiFi / portable hotspots - pocket-sized battery-powered units that create a Wi-Fi network from a data SIM. Ideal for individuals, pop-up stands, events and temporary working.
• 4G/5G routers - mains-powered units, often with external antenna options, that serve a whole office or site like a fixed broadband router. These are the workhorses for premises connectivity.

In 2026, mobile broadband is no longer just a stopgap. Two use cases have become genuinely mainstream:

• Primary connectivity where fixed-line is poor, slow or absent - new premises waiting on a fixed install, rural sites, temporary offices, construction and pop-up retail. A 5G router where coverage is strong can deliver speeds that rival or beat the available fixed line.
• Failover / backup - a 4G/5G router that automatically takes over if the main connection drops. For any business where downtime is expensive, this is cheap insurance, and it is increasingly built into business broadband packages.

Our 5G for business guide goes deeper on where 5G genuinely changes the calculation - the short version is that coverage at your specific postcode decides everything, so check it before you commit.

Indicative business data SIM and broadband pricing

Treat these as an illustrative guide as of June 2026, ex VAT. Data SIM pricing moves constantly and depends on network, data tier, line count and negotiation - which is why we compare live deals across the networks rather than relying on a static table.

The figures matter less than the principle: a router carrying a site's whole internet needs a very different plan from a sensor that pings home once a day, and putting them both on the same default tier wastes money on one and starves the other.

The pooling opportunity most businesses miss

Here is where I most often find money on the table. Data SIMs are usually bought one at a time, as devices are added - a tablet here, a router there, an IoT SIM with a new terminal - each on its own separately-guessed plan, none of them pooled with each other or with the company's phone SIMs. The result is a scattered set of allowances, some near their limit and some barely touched, with no shared buffer.

The fix is to bring data SIMs into the same pooled allowance as the rest of the estate wherever the network allows it. Light IoT lines and barely-used tablets then contribute their unused data to the pool, heavy routers draw from it, and overage largely disappears - you buy one right-sized bucket instead of a dozen wrong-sized ones. The mechanics are identical to phone-SIM pooling, covered in our data pooling guide. Treating data SIMs as part of the mobile estate, not a separate afterthought, is the single biggest lever here.

Matching the SIM to the device

Buy on the use case, not a default tier:

• IoT and M2M devices - low-data plans, often with long contract terms suited to fixed kit. Many networks offer dedicated IoT tariffs; the key is a small, cheap allowance plus aggregation across many devices.
• Tablets and laptops - mid-data plans sized on how the device is actually used. A boardroom tablet on Wi-Fi needs little; a field laptop tethering all day needs a lot.
• Mobile broadband routers - high-data or unlimited, especially if the router is a primary connection or backup that may carry full traffic during an outage. Skimping here defeats the purpose.
• Backup/failover SIMs - need enough headroom to carry real traffic during an outage, even if they sit idle most of the time. Size for the bad day, not the average one.

And as with any business SIM, check coverage at the device's actual location before committing - a data SIM is only as good as the signal where the device lives. Our network comparison covers the EE/Vodafone/O2 decision and the importance of checking Ofcom's coverage data at your postcodes.

Security and management for data SIMs

Data-only devices are easy to forget about, which makes them a soft spot:

• Spend caps and alerts. A router or tethering SIM can burn through data fast; caps stop a misconfigured device producing a shock bill.
• Inventory. Track every data SIM against its device. The classic waste is a SIM still billing for a router that was decommissioned months ago.
• Security on connected devices. Routers and IoT kit need their own security hygiene - default passwords changed, firmware updated. Our mobile security best practices guide applies here too.
• Review at renewal. Fold data SIMs into the same renewal review as your handsets so they are right-sized and pooled, not left drifting.

How to buy business data SIMs well: a checklist

• List every connected device that needs data - tablets, laptops, routers, IoT, backup lines.
• Size each by actual use case, not a default tier.
• Pool them with the wider estate wherever the network allows.
• Check coverage at each device's location before committing.
• Set spend caps on routers and tethering SIMs.
• Keep an inventory so decommissioned devices stop billing.
• Review at renewal alongside your phone SIMs.

The bottom line

Business data SIMs and mobile broadband are a real and growing part of the connectivity estate - powering tablets, routers, 5G broadband and a long tail of IoT - and in 2026 a 5G router is a genuine primary or backup connection where coverage is strong. The mistake is buying them ad hoc, one device at a time, on separate guessed plans. Treat data SIMs as part of the mobile estate: size each to its use case, pool them with your handsets, cap the routers, and review them at renewal. If you want your data SIMs and mobile broadband priced and pooled alongside your handsets, get a business mobile quote and we will compare the whole estate across EE, Vodafone and O2.