All 4 UK networks vs one
Fuse data uses all four UK networks (EE, Vodafone, Three, O2) automatically. giffgaff is an MVNO on O2 only — your coverage depends entirely on O2 wherever you are.
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Fuse vs giffgaff
Fuse Mobile and giffgaff are both eSIM options in the UK. The difference is network reach: Fuse uses all four UK networks with automatic switching to the strongest; giffgaff runs on O2 only. Here's the comparison — all giffgaff facts verified from giffgaff.com on 4 June 2026.
| Feature | Fuse | giffgaff |
|---|---|---|
| Product | UK multi-network data-only eSIM | UK mobile service on O2 (MVNO) |
| UK networks | All 4 (EE, Vodafone, Three, O2) | O2 only |
| Multi-network switching | ||
| Data — apps you can use | Any app, any service. Standard unrestricted data. | Any app, any service. Standard unrestricted data. |
| Banking, social, streaming, VPN, gaming | ||
| Starting price | From £5.99/mo for 5GB | From £6/mo for 1GB goodybag |
| International roaming | 130+ countries on Pulse and Surge | 37 EU/EEA destinations, 5GB cap |
| eSIM | ||
| Contract | Monthly rolling, cancel any time | Rolling monthly goodybags |
Product
FuseUK multi-network data-only eSIM
giffgaffUK mobile service on O2 (MVNO)
UK networks
FuseAll 4 (EE, Vodafone, Three, O2)
giffgaffO2 only
Multi-network switching
Fuse
giffgaff
Data — apps you can use
FuseAny app, any service. Standard unrestricted data.
giffgaffAny app, any service. Standard unrestricted data.
Banking, social, streaming, VPN, gaming
Fuse
giffgaff
Starting price
FuseFrom £5.99/mo for 5GB
giffgaffFrom £6/mo for 1GB goodybag
International roaming
Fuse130+ countries on Pulse and Surge
giffgaff37 EU/EEA destinations, 5GB cap
eSIM
Fuse
giffgaff
Contract
FuseMonthly rolling, cancel any time
giffgaffRolling monthly goodybags
giffgaff data in the table above was verified from giffgaff's own published pages on 4 June 2026. Pricing and promotional terms change frequently — please re-check giffgaff's website for current details before deciding.
Sources: Goodybags + plans·Why giffgaff (O2 network)·Roaming charges·eSIM support
Why Fuse
What Fuse offers.
Strongest signal wins
Fuse scans all four networks continuously and moves to whichever is strongest in under a second. With giffgaff you stay on O2 — if O2 is weak in your area, your data stays weak.
No weak-zone problem
Single-network providers have coverage maps with gaps. Fuse fills those gaps with the other three networks — when one weakens, another takes over before you notice.
Wider roaming reach
Fuse Pulse and Surge plans include data in 130+ countries. giffgaff's "Roam Like at Home" covers 37 EU/EEA destinations with a 5GB cap from your plan.
Fuse is a UK multi-network data-only eSIM — one digital SIM that uses all four UK networks (EE, Three, Vodafone, O2) and switches automatically to whichever has the strongest signal. Fuse does not issue a phone number; giffgaff does. Most customers keep giffgaff for calls and SMS on their existing number, and add Fuse alongside via dual-SIM to handle data.
Yes. Every eSIM-capable phone (most flagships from 2018 onwards) supports dual-SIM — one physical SIM and one eSIM, or two eSIMs. Keep giffgaff for calls and SMS, install Fuse as a second eSIM for data. Both lines work at the same time.
No. Fuse is data-only — there is no number, no carrier voice calls, no SMS. Apps like WhatsApp, FaceTime, iMessage and Signal work normally over the Fuse data line. Your existing giffgaff number stays where it is.
No — Fuse is rolling monthly. Cancel or change plan any month with no exit fees. Plans start at £5.99/month for Spark (5GB), £9.99 for Pulse (10GB plus roaming in 130+ countries), and £14.99 for Surge (15GB plus roaming).
Done comparing?
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