UK eSIM guide: networks, coverage and setup

• EE (BT)Largest network; strong national coverage.
• Virgin Media O2Major nationwide network.
• VodafoneThreeFormed in 2025 from Vodafone and Three; the two brands still run separately while the networks are integrated.

5G5G is widely available in cities; 3G networks have been switched off, so phones need 4G calling (VoLTE).

• The UK left the EU roam-like-at-home scheme after Brexit; always confirm UK coverage in a Europe plan.
• The London Underground is getting 4G/5G in stages; about 60% of underground stations had coverage by mid-2026, with full coverage targeted by end-2026. The Elizabeth line is fully covered.

Prepaid (pay-as-you-go) SIMs are sold in supermarkets, newsagents and at airports. No ID or registration is required.

Weak-signal areas

Good in cities. Scottish Highlands, Lake District, Snowdonia (Eryri) and other rural areas have gaps; some Tube tunnels still have none.