Three Business Mobile Deals: SIM Only and Team Plans

Reviewed: 16 September 2026

Compare Three business mobile deals around your team's coverage, devices and data needs. Start with SIM only for existing phones, handset contracts for replacements, and an itemised multi-line quote for teams. Check roaming and the full contract cost before deciding.

Compare The Networks is a UK business telecoms comparison service. Request a free, no-obligation business quote to compare suitable options alongside other networks.

Which Three business option should you compare?

What your team needs	Option to consider	Key check
Airtime for existing phones	Business SIM only	Device compatibility, data and coverage
Replacement work phones	Handset and airtime proposal	Model, storage, upfront charge and total repayments
Several business lines	Multibuy or a team quote	Price per line, eligibility and renewal dates
Staff who travel	A plan with the appropriate roaming option	Countries, fair-use limits and excluded usage
A larger fleet	An account proposal matched to the workforce	Administration, reporting and support requirements

Three publishes business SIM only plans and multibuy SIM options. Availability and terms depend on the offer. Quotes arranged through this site have a minimum contract term of 24 months.

Unlimited UK data and roaming are different

Three offers business SIM plans with different UK data allowances, including unlimited options. Choose based on current usage and the work people need to do, including any hotspot use.

For staff travelling overseas, Three publishes several inclusive roaming options. The destinations and fair-use limits depend on the plan. An unlimited UK allowance does not mean unlimited overseas data, and a roaming pass should not be assumed to cover every destination or type of call.

List the countries and expected travel days in the quote request. Ask for the relevant country list, data allowance and any daily charge in writing for each travelling user's SIM.

Check coverage at the places you work

Use Three's coverage checker for the office, home-working addresses and regular job sites. Treat predicted coverage as a starting point and ask how you can check the service in important indoor locations.

Reception and performance depend on the location, building, device and network conditions. Avoid choosing a whole fleet using a national speed claim alone. Compare the result with the EE, O2 and Vodafone options relevant to your team.

What belongs in a complete Three business quote?

The monthly price for every line and whether VAT is included.
Exact handset model, storage and upfront or separate device payments.
UK data, call and text allowances, plus extra-usage rates.
Roaming products, destinations, limits and charges.
Contract length, price changes and renewal date for each line.
Multibuy eligibility and the conditions attached to any discount.
Support arrangements, account controls and who issues the bill.
The process for keeping existing numbers and any current exit charges.

Compare proposals over the same period. A cheaper first-month price can cost more over the full term, and a discount is only useful if the underlying plan fits the team's needs.

Frequently asked questions

Does Three offer business SIM only deals?

Yes. Three publishes business SIM only options with different data allowances and inclusive roaming choices. Check the exact offer and eligibility when requesting your quote.

Are Three business deals always the cheapest?

No single network is always the lowest-cost suitable option. Compare devices, allowances, coverage, roaming and charges across the full contract term.

Can a team get a multi-line deal?

Three publishes multibuy options. Ask which lines qualify, whether different allowances can be combined, and what happens if the team size changes. Do not assume a fixed saving for every account.

Is international roaming included?

Some business plans include specified roaming options. Check the destination list, fair-use limit and charge conditions for your particular tariff before travelling.

Can we keep our mobile numbers?

Ask the receiving supplier to confirm the transfer process for the account and agree the timing. Check existing commitments before making the switch.