Range holder · Ofcom numbering snapshot published 14 Oct 2026
BT: Ofcom-listed range holder, not evidence of who called
What does Ofcom list for BT?
BT is listed by Ofcom as the holder of 20,692 number blocks (122,509,801 numbers) in the snapshot published 14 Oct 2026, across 596 area codes and 5 number families (geographic, 03, 09, 08, 05). 12 of its blocks carry an allocation date in the last 12 months. Check the number below.
Did not expect the call? Do not call back; contact the organisation on a number you find yourself.
A range holder is usually a network or wholesale provider that supplies numbers to other businesses. This Ofcom listing records an allocation only; it is not evidence about the range holder or caller. A number ported to another network still shows its original range holder here.
If a caller ID shows a BT number and you did not expect the call, do not call back; contact the organisation you think it was on a number you find yourself.
| Status | Blocks |
|---|---|
| Allocated | 17,577 |
| Allocated (Closed Range) | 3,115 |
| Quarantined, still listed | 0 |
| Quarantined, no longer listed since 19 Aug 2026 | 54 |
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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Check the number privately
Enter a number below. The lookup runs privately in your browser and returns the Ofcom block status with a callback rule.
Local lookup
Enter the number that called
Your full number does not leave this page. A lookup downloads only the relevant four-digit prefix-class file.
| Lookup | Method |
|---|---|
| Ofcom block | Private lookup in this browser |
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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What should I do after an unexpected call?
BT is the range holder, not necessarily the organisation that called: numbers in its blocks are often used by its business customers.
| Step | Action |
|---|---|
| 1 | Do not call back a number you cannot identify. If it rang once and cut off, that is often a test that your line is live. |
| 2 | If the caller said they were your bank, a company or the police, hang up and phone the organisation on a number you find yourself, or call 159 for your bank. |
| 3 | Forward suspicious text messages to 7726, free of charge. |
| 4 | If you lost money or shared details, contact your bank at once and report to Action Fraud (England, Wales and Northern Ireland) or Police Scotland. |
| 5 | For unwanted marketing calls, report to the ICO and block the number on your phone. |
| 6 | Calls to 01 and 02 numbers are charged at your provider’s standard landline rate (gov.uk/call-charges). |
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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Which kinds of numbers does BT hold?
Of the 122,509,801 numbers listed to BT in the snapshot published 14 Oct 2026, 89.8% are geographic numbers. The chart shows how its own numbers split across number families.
| Family | Numbers | Blocks | Share of this holder's numbers |
|---|---|---|---|
| geographic | 110,052,400 | 16,501 | 89.8% |
| 03 | 4,235,000 | 428 | 3.5% |
| 09 | 3,940,000 | 394 | 3.2% |
| 08 | 3,642,401 | 3,305 | 3.0% |
| 05 | 640,000 | 64 | 0.5% |
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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Which area codes are BT numbers in?
BT holds blocks in 596 UK area codes. The table lists the 10 codes where it holds the most numbers, with the place Ofcom lists for each; the full list is in the CSV.
| Area code | Place | Numbers | Blocks |
|---|---|---|---|
| 020 | London | 13,440,000 | 1,344 |
| 028 | Ballycastle, Martinstown, Ballymena, Ballymoney, Larne, Kilrea, Newry, Armagh, Portadown, Banbridge, Rostrevor, Kircubbin, Newcastle (Co. Down), Downpatrick, Enniskillen, Lisnaskea, Kesh, Coleraine, Londonderry, Limavady, Magherafelt, Carrickmore, Newtownstewart, Omagh, Ballygawley, Cookstown, Dungannon, Fivemiletown, Belfast, Bangor (Co. Down), Lisburn, Ballyclare, Antrim, Saintfield | 2,887,000 | 349 |
| 0161 | Manchester | 2,730,000 | 273 |
| 0121 | Birmingham | 2,260,000 | 226 |
| 0151 | Liverpool | 1,730,000 | 173 |
| 0191 | Tyneside, Durham, Sunderland | 1,730,000 | 173 |
| 0141 | Glasgow | 1,640,000 | 164 |
| 023 | Southampton, Portsmouth | 1,140,000 | 114 |
| 0113 | Leeds | 1,050,000 | 105 |
| 0131 | Edinburgh | 990,000 | 99 |
and 586 more in the CSV
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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Has anything changed in BT’s blocks, and what was allocated recently?
Between the weekly Ofcom files fetched on 19 Aug 2026 and 17 Oct 2026, 56 blocks listed to BT at some point changed status or holder; a block with several changes counts once. 12 of its blocks have an allocation date in the last 12 months.
Ofcom: “Please note that transferred numbers will also be shown as ‘allocated’.” (numbering data, ofcom.org.uk, retrieved 24 Sep 2026)
| Weekly transition | Changed blocks |
|---|---|
| 2026-08-19 – 2026-08-26 | 12 |
| 2026-08-26 – 2026-09-02 | 0 |
| 2026-09-02 – 2026-09-09 | 11 |
| 2026-09-09 – 2026-09-16 | 12 |
| 2026-09-16 – 2026-09-24 | 0 |
| 2026-09-24 – 2026-09-30 | 21 |
| 2026-09-30 – 2026-10-07 | 0 |
| 2026-10-07 – 2026-10-17 | 0 |
BT blocks with an allocation date in the last 12 months, snapshot published 14 Oct 2026 · 12 blocks
| Block | Recorded allocation date | Code | Numbers |
|---|---|---|---|
| 1218 35 | 2026-07-24 | 0121 | 10,000 |
| 1697 34 77 | 2026-06-30 | 01697 | 100 |
| 1615 73 | 2026-05-26 | 0161 | 10,000 |
| 2866 62 4 | 2026-05-06 | 028 | 1,000 |
| 2896 02 7 | 2026-03-12 | 028 | 1,000 |
| 2896 02 8 | 2026-03-12 | 028 | 1,000 |
| 2896 02 9 | 2026-03-12 | 028 | 1,000 |
| 1135 51 | 2025-12-04 | 0113 | 10,000 |
and 4 more in the CSV
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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Since when has BT held its number blocks?
The earliest allocation date recorded for BT’s blocks is 1994; 1,087 of its 20,692 blocks carry a date from 2020 onwards. Recorded dates are provisional: a block that moved to another provider may show the date of that move rather than its first allocation.
| Recorded years | Allocated blocks |
|---|---|
| 1994–1999 | 11,029 |
| 2000–2004 | 3,070 |
| 2005–2009 | 1,251 |
| 2010–2014 | 3,440 |
| 2015–2019 | 652 |
| 2020–2024 | 1,013 |
| 2025–2029 | 74 |
| No recorded date | 163 |
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV
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Where do these numbers come from, and how do I cite this page?
Rangecheck, “BT — Ofcom numbering snapshot published 14 Oct 2026”, release fc227d9e, https://rangecheck.co.uk/operators/bt/, retrieved 24 Sep 2026. Contains Ofcom copyright material: numbering data (ofcom.org.uk).
How to cite · Contains Ofcom copyright material
| Field | Value |
|---|---|
| Release | fc227d9e |
| Source published | 14 Oct 2026 |
| Source fetched | 2026-10-17 20:56 UTC |
| Source files | s1.csv, s3.csv, s5.csv, s8.csv, s9.csv |
Source: Ofcom numbering data s1.csv, s3.csv, s5.csv, s8.csv, s9.csv, published 14 Oct 2026, fetched 2026-10-17 20:56 UTC, sha256 s1.csv b541ed1f, s3.csv d3daf36d, s5.csv bb94f64d, s8.csv 85a261b6, s9.csv 9a6fcf3d · n = 20,692 blocks · method: block capacity from number length · release fc227d9e · CSV