This guide answers one question for Scotland: which mobile network gives the best signal, and where the answer changes. Every figure comes from the same May 2025 coverage measurements behind NetScan's coverage checker, based on 14,555 addresses in 733 sampled postcodes across 139 Scottish postcode districts in 15 postcode areas. Nothing is estimated, and no network is called best where the data does not say so.
The short answer is that no network wins Scotland on these figures. Pooled across every district NetScan holds, the overall scores are O2 99, Three 99, Vodafone 99, EE 98 out of 100, a spread of 1 point. In 13 of the 15 postcode areas the four are within 5 points of each other. The two exceptions are both island groups: Hebrides (HS) and Shetland (ZE).
Indoor signal is where the differences are, and they are local. The lowest reading in the data is EE in DG1 (Dumfries and Galloway), where 0% of the 126 addresses sampled get good indoor signal. This guide sets out every area side by side, then the islands, then the individual districts where one network falls far behind, so you can see whether yours is one of them.
Scotland area by area: the four networks side by side
Each row pools the districts NetScan holds in one postcode area, weighted by the addresses sampled in each. They are the same overall scores the area coverage checkers show. A network is only named as leading where it is 5 or more points clear of the lowest, the same test every NetScan page uses.
'Overall' blends three measures: the share of sampled addresses at the top 'enhanced' outdoor data grade (35%), with good or better outdoor 4G (50%), and with good or better indoor signal (15%). The enhanced grade is a signal-strength grade, not a promise of 5G service on your plan.
| Area | Districts | Addresses | EE | O2 | Three | Vodafone | Verdict |
|---|---|---|---|---|---|---|---|
| Dundee (DD) | 11 | 1,116 | 100 | 100 | 100 | 100 | No winner |
| Dumfries (DG) | 9 | 666 | 96 | 99 | 99 | 99 | No winner (3 points apart) |
| Edinburgh (EH) | 20 | 2,511 | 100 | 100 | 99 | 100 | No winner (1 point apart) |
| Falkirk (FK) | 9 | 967 | 97 | 100 | 99 | 100 | No winner (3 points apart) |
| Glasgow (G) | 11 | 1,750 | 100 | 100 | 100 | 100 | No winner |
| Hebrides (HS) | 6 | 499 | 97 | 83 | 94 | 89 | EE highest (97); O2 lowest (83) |
| Inverness (IV) | 9 | 900 | 97 | 97 | 97 | 96 | No winner (1 point apart) |
| Kilmarnock (KA) | 9 | 858 | 99 | 100 | 99 | 100 | No winner (1 point apart) |
| Kirkwall (KW) | 8 | 472 | 96 | 94 | 94 | 97 | No winner (3 points apart) |
| Kirkcaldy (KY) | 9 | 1,047 | 97 | 100 | 99 | 100 | No winner (3 points apart) |
| Motherwell (ML) | 9 | 1,082 | 99 | 100 | 99 | 100 | No winner (1 point apart) |
| Paisley (PA) | 9 | 991 | 100 | 100 | 98 | 100 | No winner (2 points apart) |
| Perth (PH) | 9 | 770 | 98 | 98 | 99 | 98 | No winner (1 point apart) |
| Galashiels (TD) | 9 | 662 | 98 | 99 | 99 | 99 | No winner (1 point apart) |
| Shetland (ZE) | 2 | 264 | 93 | 99 | 94 | 97 | O2 highest (99); EE lowest (93) |
Overall score out of 100, based on 14,555 addresses in 733 postcodes (May 2025 data).
Indoor signal across Scotland: where the networks part company
Outdoors the mainland areas are level: good outdoor 4G reaches every sampled address for all four networks in every one of the 13 areas where no network leads. Indoor signal is what separates them. Pooled across every district held, good indoor signal reaches at O2 95%, Vodafone 95%, Three 93%, EE 90% of sampled addresses.
The network trailing its area's best indoor figure by 5 or more points is most often EE: in Dumfries, Falkirk, Inverness, Kirkcaldy, Motherwell, Perth, Galashiels and Shetland. Three trails in Falkirk, Hebrides, Kilmarnock, Kirkcaldy, Paisley and Shetland; Vodafone trails in Hebrides, Inverness, Perth and Shetland; O2 trails in Hebrides, Kirkwall and Perth. An area figure is an average, though: the district table further down shows where the big gaps actually sit.
At the other end, Glasgow is level on every measure: all four networks reach good indoor signal at 100% of sampled addresses in every district NetScan holds there.
| Area | EE | O2 | Three | Vodafone | 5+ behind |
|---|---|---|---|---|---|
| Dundee (DD) | 100% | 97% | 100% | 98% | None |
| Dumfries (DG) | 72% | 93% | 92% | 94% | EE |
| Edinburgh (EH) | 100% | 99% | 96% | 100% | None |
| Falkirk (FK) | 79% | 100% | 94% | 100% | EE and Three |
| Glasgow (G) | 100% | 100% | 100% | 100% | None |
| Hebrides (HS) | 85% | 70% | 77% | 68% | O2, Three and Vodafone |
| Inverness (IV) | 77% | 81% | 83% | 77% | EE and Vodafone |
| Kilmarnock (KA) | 96% | 99% | 93% | 100% | Three |
| Kirkwall (KW) | 81% | 72% | 82% | 81% | O2 |
| Kirkcaldy (KY) | 79% | 97% | 92% | 100% | EE and Three |
| Motherwell (ML) | 91% | 97% | 96% | 100% | EE |
| Paisley (PA) | 100% | 100% | 88% | 100% | Three |
| Perth (PH) | 84% | 87% | 93% | 85% | EE, O2 and Vodafone |
| Galashiels (TD) | 89% | 97% | 93% | 96% | EE |
| Shetland (ZE) | 51% | 96% | 71% | 79% | EE, Three and Vodafone |
Good or better indoor data signal, share of sampled addresses. The last column names each network 5 or more points behind the area's best indoor figure. May 2025 data.
The Western Isles (Hebrides, HS): where the four networks separate
Across the 6 Western Isles districts NetScan holds, EE scores highest overall at 97/100 and O2 lowest at 83/100, a spread of 14 points across 499 sampled addresses. That is wide enough to call, unlike every mainland area. Three is within 3 points of EE (94/100), so the top two are effectively level.
The island-wide scores hide how much this changes between districts. The network lowest indoors is Vodafone in HS4 (Harris); Three in HS5 (Harris); Vodafone in HS7 (Benbecula); Three in HS8 (South Uist); O2 in HS9 (Barra). Check the district you live in or are visiting, not the island group as a whole. HS8 rests on fewer than 30 sampled addresses, so treat that row with care.
| District | Place | Addresses | EE | O2 | Three | Vodafone |
|---|---|---|---|---|---|---|
| HS1 | Stornoway | 50 | 100% | 100% | 100% | 100% |
| HS4 | Harris | 90 | 82% | 19% | 83% | 11% |
| HS5 | Harris | 90 | 97% | 100% | 73% | 97% |
| HS7 | Benbecula | 102 | 100% | 94% | 100% | 89% |
| HS8 | South Uist | 29 | 28% | 90% | 0% | 97% |
| HS9 | Barra | 138 | 76% | 51% | 65% | 52% |
Good or better indoor data signal, share of sampled addresses. NetScan holds 6 of 9 Hebrides districts. May 2025 data.
Shetland (ZE): where the four networks separate
Across the 2 Shetland districts NetScan holds, O2 scores highest overall at 99/100 and EE lowest at 93/100, a spread of 6 points across 264 sampled addresses. That is wide enough to call, unlike every mainland area. Vodafone is within 2 points of O2 (97/100), so the top two are effectively level.
The island-wide scores hide how much this changes between districts. The network lowest indoors is EE in ZE1 (Lerwick); Three in ZE3 (south Shetland). Check the district you live in or are visiting, not the island group as a whole.
| District | Place | Addresses | EE | O2 | Three | Vodafone |
|---|---|---|---|---|---|---|
| ZE1 | Lerwick | 151 | 21% | 93% | 98% | 64% |
| ZE3 | south Shetland | 113 | 92% | 99% | 35% | 100% |
Good or better indoor data signal, share of sampled addresses. NetScan holds 2 of 3 Shetland districts. May 2025 data.
The Scottish districts with the lowest indoor readings
These are the ten lowest good-indoor readings in the 139 districts, counting only districts with at least 30 addresses sampled in at least 3 postcodes. In all ten, the same network reaches good outdoor 4G at every sampled address: the gap is inside buildings. Each district figure comes from a handful of sampled postcodes (the count is in the table), so treat it as a strong hint about your street, not a verdict on it.
| District | Place | Network | Good indoor | Addresses | Postcodes |
|---|---|---|---|---|---|
| DG1 | Dumfries and Galloway | EE | 0% | 126 | 5 |
| FK2 | Falkirk | EE | 1% | 109 | 5 |
| IV5 | Highland | EE | 2% | 53 | 5 |
| IV5 | Highland | Three | 2% | 53 | 5 |
| IV5 | Highland | Vodafone | 2% | 53 | 5 |
| IV5 | Highland | O2 | 8% | 53 | 5 |
| HS4 | Harris | Vodafone | 11% | 90 | 5 |
| IV9 | Highland | Vodafone | 16% | 112 | 6 |
| TD9 | Scottish Borders | Vodafone | 18% | 33 | 5 |
| HS4 | Harris | O2 | 19% | 90 | 5 |
Good or better indoor data signal, share of sampled addresses. Districts with fewer than 30 addresses or 3 postcodes sampled are left out of this list. May 2025 data.
Choosing a network in Scotland with this data
Start with your district, not the country or even the area. If your district is in the table above, the network listed there is the one to check hardest, especially if you use your phone mostly indoors. If your area is one where no network leads and your district is not listed, coverage gives you little reason to prefer one network, so the decision moves to price, contract length and roaming.
The network you choose also decides which SIM brands you can use: giffgaff and Tesco Mobile run on O2's masts; SMARTY and iD Mobile on Three's; VOXI, Talkmobile and Lebara on Vodafone's; and 1pMobile on EE's. A SIM brand gets its host network's coverage, so every figure in this guide applies to it too. Plan prices change often, so check the provider's own site for today's price.
What these figures cover, and what they don't
NetScan does not hold coverage figures for every part of Scotland. It holds no Aberdeen (AB) districts at all, so Aberdeen and Aberdeenshire are missing from every table here. In most other areas it holds only the lower-numbered districts, usually 1 to 9, which means large parts of the Highlands, Argyll, Orkney and the Borders are not in the data: for example, the Kirkwall (KW) figures are for the Caithness and Sutherland districts KW1 to KW9, not for Orkney. Two island areas are also incomplete: Hebrides (6 of 9) and Shetland (2 of 3) districts held. Where a place is not covered, this guide says nothing about it.
The data is a prediction of signal at each sampled address, not a speed test, and the sample per district ranges from 5 to 330 addresses. Indoor signal depends heavily on the building: thick stone walls, basements and foil-backed insulation all cut it. Run your full postcode through NetScan's scanner, then confirm on the operator's own coverage checker. If indoor signal is the problem at home, Wi-Fi calling on a compatible phone and plan routes calls over your broadband instead.