Compare O2 SIM Only Deals

O2 runs its own network rather than piggybacking on another operator, so when you buy an O2 SIM you are dealing with the network directly. That includes 5G in the places O2 has rolled it out, on a plan and phone that support it. Coverage is the thing to nail down first, so check the O2 signal at your home, workplace and usual routes before you commit to a plan.

O2 offers both flexible plans and longer contract plans, so you can pick the level of commitment that suits you. Flexible options give you room to change things up, while contract plans typically lock in a set monthly cost for a fixed term. The live deals above show the current allowances, contract lengths and prices, so you can line them up and choose based on your usage.

O2 adds a fixed amount to pay monthly bills every April, set out in pounds and pence in the contract summary. Our guide to SIM only mid-contract price rises explains the amounts and when you can leave without a fee.

The standout extra is O2 Priority, the rewards programme that offers deals, prize draws and early access to event tickets. If you are a Virgin Media customer, Volt benefits can add value across your services too. Because the exact perks attached to each plan can differ, it is worth reading the deal terms in the comparison above so you know what comes with the option you pick.

O2 suits people who want to deal with a main network directly and value its rewards, especially O2 Priority and, for Virgin Media customers, Volt benefits. The choice of flexible and contract plans means there is something for both the commitment-shy and those after a fixed monthly cost. If your top priority is the lowest possible price, the cheaper networks on the same O2 infrastructure are worth weighing up.

You do not have to go direct to ride O2's network. giffgaff, Sky Mobile and Tesco Mobile all use the same network, often at lower prices, though without O2 Priority or Volt. The trade-off is rewards versus cost: buy direct from O2 for the full feature set, or pick one of those if budget leads.