giffgaff
eSIMUK MVNO on O2 — near-zero-cost UK number you can keep alive from China
Best for: Cloud residents who want a UK number for registrations, receiving SMS and light roaming use at near-zero annual cost.
Overview
giffgaff is a UK MVNO running on O2's network. Order a free SIM, top up £10 to activate on Pay as you go, then swap to eSIM in the giffgaff app. Keep the number alive with any balance change (e.g. one £0.30 SMS) every 180 days; roaming in mainland China works out of the box.
giffgaff is the classic choice for a low-cost UK number that keeps working while you live in mainland China.
Activation: order the free SIM on the official site (note: giffgaff has stopped shipping physical SIMs to China — choose eSIM in the app instead), top up £10 with a Visa/Mastercard credit card and pick Pay as you go; the £5 joiner credit is the standard refer-a-friend reward and requires activating via a referral link (as of Sept 2026 — the August 2026 £10 "Double Reward" promo ended 31 Aug 2026). Number-keeping rule: any balance change within each 180-day window (a top-up or any charged usage — one £0.30 SMS is enough) resets the clock; miss it and the number is recycled with no refund. Converting a physical card to eSIM happens in the giffgaff app under SIM management and requires passing IMEI verification of your phone.
In mainland China the SIM roams with signal right after activation, supports Wi-Fi Calling, and data packs can be added on demand. No real-name ID is required for ordering. Watch-outs: the £5 referral credit is forfeited if the 180-day rule is missed; customer service is community/app based with no physical stores.
New since July 2026 — roaming fair-use crackdown: terms clause 2.9 permits use in the EU and selected destinations only for periodic travel (holidays, short breaks). Since late July 2026 giffgaff has been bulk-disconnecting SIMs used for long-term roaming outside the UK under this clause ("We're disconnecting your service" notices). Long-term China-based use therefore carries a real disconnection risk — do not rely on giffgaff as your only number.
Popular plans
| Plan | Data from | Validity | Price |
|---|---|---|---|
| Pay as you go (keep-alive base) | Pay per use | 180 days per activity | £10 first top-up (£5 joiner credit only via referral link); one £0.30 SMS per 180 days keeps it alive |
Prices as published by giffgaff (2026-03 source review); data goodybags are optional add-ons, not required for number keeping.
Pros
- Cheapest mainstream UK number to keep alive (£0.30 SMS / 180 days)
- First top-up £10 + £5 joiner credit via referral link
- Works in mainland China right after activation, Wi-Fi Calling supported
- No real-name registration required
Things to note
- Missing the 180-day activity window forfeits the number and all credit
- Official SIM shipping to China has stopped — eSIM app flow required
- Community-based support, no physical stores
- Since July 2026, terms clause 2.9 fair-use enforcement has bulk-disconnected SIMs roaming outside the UK long-term — a real risk for China-based keep-alive
Key features
- Free SIM order, £10 activation top-up (£5 joiner credit via referral link)
- Any balance change per 180 days keeps the number alive
- eSIM swap inside the giffgaff app (IMEI verification)
- No real-name ID required; Wi-Fi Calling supported