rangecheck

0204 area code: London numbers starting 020 4

0204 is not a separate area code. It is London (020) followed by local numbers starting 4.

1,550,000 numbers are allocated in 155 blocks to 50 listed holders (Ofcom, 14 Oct 2026).

Check a 0204 number privately

Number ranges registered under 020 4

020 4 blocks: holder, status and allocation date
Number rangeListed holderStatusAllocation date
020 45000000 – 020 45009999 Syntec Limited Allocated 2019-10-18
020 45010000 – 020 45019999 TalkTalk Communications Limited Allocated 2020-01-09
020 45020000 – 020 45029999 Magrathea Telecommunications Limited Allocated 2019-11-12
020 45030000 – 020 45039999 Hyperoptic Ltd Allocated 2020-01-07
020 45040000 – 020 45049999 DRD Communications Limited Allocated 2023-10-05
020 45050000 – 020 45059999 BT Allocated 2020-01-07
020 45060000 – 020 45069999 BT Allocated 2020-01-07
020 45070000 – 020 45079999 Verizon UK Limited Allocated 2020-02-06
020 45080000 – 020 45089999 Odigo Allocated 2020-03-16
020 45090000 – 020 45099999 Gamma Telecom Holdings Limited Allocated 2020-03-24
020 45100000 – 020 45109999 Colt Technology Services Allocated 2020-02-25
020 45110000 – 020 45119999 Gamma Telecom Holdings Limited Allocated 2020-05-27
020 45120000 – 020 45129999 BT Allocated 2020-04-09
020 45130000 – 020 45139999 Gamma Telecom Holdings Limited Allocated 2020-02-25
020 45140000 – 020 45149999 Colt Technology Services Allocated 2020-03-30
020 45150000 – 020 45159999 Colt Technology Services Allocated 2020-02-25
020 45160000 – 020 45169999 BT Allocated 2020-04-09
020 45170000 – 020 45179999 BT Allocated 2020-04-09
020 45180000 – 020 45189999 Colt Technology Services Allocated 2020-05-19
020 45190000 – 020 45199999 Colt Technology Services Allocated 2020-05-27
020 45200000 – 020 45209999 TELNYX UK LIMITED Allocated 2020-04-28
020 45210000 – 020 45219999 Colt Technology Services Allocated 2020-05-27
020 45220000 – 020 45229999 Colt Technology Services Allocated 2020-05-27
020 45230000 – 020 45239999 Colt Technology Services Allocated 2020-07-01
020 45240000 – 020 45249999 Gamma Telecom Holdings Limited Allocated 2020-08-19
020 45250000 – 020 45259999 Voxbone SA Allocated 2020-04-24
020 45260000 – 020 45269999 Colt Technology Services Allocated 2020-07-01
020 45270000 – 020 45279999 Media Hawk Ltd Allocated 2020-07-28
020 45280000 – 020 45289999 Colt Technology Services Allocated 2020-08-24
020 45290000 – 020 45299999 BT Allocated 2020-08-24
020 45300000 – 020 45309999 Gamma Telecom Holdings Limited Allocated 2020-09-16
020 45310000 – 020 45319999 BT Allocated 2020-10-13
020 45320000 – 020 45329999 Colt Technology Services Allocated 2020-10-08
020 45330000 – 020 45339999 GCI Network Solutions Limited Allocated 2023-12-22
020 45340000 – 020 45349999 Colt Technology Services Allocated 2020-09-30
020 45350000 – 020 45359999 EG TECHNOLOGIES LIMITED Allocated 2020-01-21
020 45360000 – 020 45369999 Colt Technology Services Allocated 2020-09-30
020 45370000 – 020 45379999 BT Allocated 2020-10-13
020 45380000 – 020 45389999 Twilio Ireland Limited Allocated 2020-09-15
020 45390000 – 020 45399999 BT Allocated 2020-10-13
020 45400000 – 020 45409999 Colt Technology Services Allocated 2019-10-14
020 45410000 – 020 45419999 BT Allocated 2020-12-07
020 45420000 – 020 45429999 Gamma Telecom Holdings Limited Allocated 2020-11-10
020 45430000 – 020 45439999 9EONS LIMITED Allocated 2020-12-16
020 45440000 – 020 45449999 Planet Telecom Ltd Allocated 2019-10-08
020 45450000 – 020 45459999 AQL Wholesale Ltd Allocated 2019-10-08
020 45460000 – 020 45469999 Spitfire Network Services Limited Allocated 2019-12-09
020 45470000 – 020 45479999 Hyperoptic Ltd Allocated 2020-12-30
020 45480000 – 020 45489999 Gamma Telecom Holdings Limited Allocated 2021-01-08
020 45490000 – 020 45499999 Gamma Telecom Holdings Limited Allocated 2021-01-12
020 45500000 – 020 45509999 Global Reach Networks Limited Allocated 2019-10-07
020 45510000 – 020 45519999 Colt Technology Services Allocated 2021-01-12
020 45520000 – 020 45529999 Colt Technology Services Allocated 2020-12-03
020 45530000 – 020 45539999 Voiceflex Limited Allocated 2021-01-22
020 45540000 – 020 45549999 Node4 Ltd Allocated 2019-11-26
020 45550000 – 020 45559999 Core Telecom Limited Allocated 2019-10-21
020 45560000 – 020 45569999 CINOS LIMITED Allocated 2021-02-03
020 45570000 – 020 45579999 Orange Business Holdings UK Limited Allocated 2021-05-06
020 45580000 – 020 45589999 Colt Technology Services Allocated 2021-03-23
020 45590000 – 020 45599999 BT Allocated 2021-03-08
020 45600000 – 020 45609999 Colt Technology Services Allocated 2020-11-06
020 45610000 – 020 45619999 Colt Technology Services Allocated 2020-11-06
020 45620000 – 020 45629999 Colt Technology Services Allocated 2020-11-06
020 45630000 – 020 45639999 Colt Technology Services Allocated 2020-11-06
020 45640000 – 020 45649999 Colt Technology Services Allocated 2020-11-06
020 45650000 – 020 45659999 Colt Technology Services Allocated 2020-11-06
020 45660000 – 020 45669999 Colt Technology Services Allocated 2020-11-06
020 45670000 – 020 45679999 Windsor Telecom Limited Allocated 2019-10-14
020 45680000 – 020 45689999 BT Allocated 2021-03-08
020 45690000 – 020 45699999 Buzz Networks Limited Allocated 2021-05-11
020 45700000 – 020 45709999 Colt Technology Services Allocated 2021-07-05
020 45710000 – 020 45719999 Voxbone SA Allocated 2021-09-16
020 45720000 – 020 45729999 Twilio Ireland Limited Allocated 2021-10-13
020 45730000 – 020 45739999 Comms Solutions Limited Allocated 2022-01-18
020 45740000 – 020 45749999 Colt Technology Services Allocated 2021-08-12
020 45750000 – 020 45759999 JAINTEL LIMITED Allocated 2021-07-28
020 45760000 – 020 45769999 Colt Technology Services Allocated 2021-08-12
020 45770000 – 020 45779999 SMARTVOICE LTD Allocated 2020-06-01
020 45780000 – 020 45789999 Belgacom International Carrier Services SA Allocated 2021-08-20
020 45790000 – 020 45799999 Voxbone SA Allocated 2022-01-17
020 45800000 – 020 45809999 SiPalto Ltd Allocated 2019-11-05
020 45810000 – 020 45819999 Gamma Telecom Holdings Limited Allocated 2022-06-30
020 45820000 – 020 45829999 Colt Technology Services Allocated 2022-02-17
020 45830000 – 020 45839999 Colt Technology Services Allocated 2022-08-08
020 45840000 – 020 45849999 Magrathea Telecommunications Limited Allocated 2021-11-10
020 45850000 – 020 45859999 Fuse 2 Communications Ltd Allocated 2021-05-06
020 45860000 – 020 45869999 Voxbone SA Allocated 2022-07-18
020 45870000 – 020 45879999 Voxbone SA Allocated 2022-07-18
020 45880000 – 020 45889999 Nuso Cloud UK Limited Allocated 2019-10-10
020 45890000 – 020 45899999 Gamma Telecom Holdings Limited Allocated 2022-10-27
020 45900000 – 020 45909999 Telet Research (NI) Limited Allocated 2021-11-01
020 45910000 – 020 45919999 Colt Technology Services Allocated 2023-06-06
020 45920000 – 020 45929999 Colt Technology Services Allocated 2023-04-20
020 45930000 – 020 45939999 Onvoy Communications Ltd. Allocated 2022-04-08
020 45940000 – 020 45949999 BT Allocated 2022-01-31
020 45950000 – 020 45959999 24 Seven Communications Limited Allocated 2021-07-13
020 45960000 – 020 45969999 SONA BUSINESS PVT. LTD. Allocated 2023-03-27
020 45970000 – 020 45979999 Hyperoptic Ltd Allocated 2023-07-20
020 45980000 – 020 45989999 KCOM Group Ltd Allocated 2022-09-08
020 45990000 – 020 45999999 Nebula Cloud Limited Allocated 2021-04-27

100 more ranges — full list in CSV.

0204 allocation

Blocks whose local number starts with 4 under London (020): 1,550,000 allocated numbers in 155 blocks.

Allocated
1,550,000 numbers · 155 blocks
Free
50,000 numbers · 5 blocks
Protected
400,000 numbers · 40 blocks

Holders of 020 4 numbers

Colt Technology Services holds 26.2% of the allocated numbers (380,000 numbers, 38 blocks).

Listed holders of 020 4 by share of allocated numbers · 14 Oct 2026
HolderShareNumbersBlocksEarliest allocation
Colt Technology Services26.2%380,000382019-10-14
Gamma Telecom Holdings Limited16.8%260,000262020-02-25
BT16.1%250,000252020-01-07
Voxbone SA5.2%80,00082020-04-24
Hyperoptic Ltd2.6%40,00042020-01-07
Twilio Ireland Limited2.6%40,00042020-09-15
Verizon UK Limited1.9%30,00032020-02-06
IOVOX Limited1.3%20,00022025-06-02
Magrathea Telecommunications Limited1.3%20,00022019-11-12
TELNYX UK LIMITED1.3%20,00022020-04-28
Voiceflex Limited1.3%20,00022021-01-22
24 Seven Communications Limited0.6%10,00012021-07-13
9EONS LIMITED0.6%10,00012020-12-16
AI Comms Ltd0.6%10,00012026-01-19
AQL Wholesale Ltd0.6%10,00012019-10-08
Belgacom International Carrier Services SA0.6%10,00012021-08-20
Buzz Networks Limited0.6%10,00012021-05-11
CINOS LIMITED0.6%10,00012021-02-03
Comms Solutions Limited0.6%10,00012022-01-18
Core Telecom Limited0.6%10,00012019-10-21
DRD Communications Limited0.6%10,00012023-10-05
Direct Market Solutions Ltd0.6%10,00012024-04-03
EG TECHNOLOGIES LIMITED0.6%10,00012020-01-21
Fuse 2 Communications Ltd0.6%10,00012021-05-06
GCI Network Solutions Limited0.6%10,00012023-12-22
Global Reach Networks Limited0.6%10,00012019-10-07
INTELLIGENT EXCHANGES LIMITED0.6%10,00012026-01-26
Inet Telecoms Ltd (Voipfone)0.6%10,00012026-10-01
JAINTEL LIMITED0.6%10,00012021-07-28
KCOM Group Ltd0.6%10,00012022-09-08
M3st Limited0.6%10,00012024-11-12
Media Hawk Ltd0.6%10,00012020-07-28
NFON UK Ltd0.6%10,00012024-05-30
Nebula Cloud Limited0.6%10,00012021-04-27
Node4 Ltd0.6%10,00012019-11-26
Nuso Cloud UK Limited0.6%10,00012019-10-10
Odigo0.6%10,00012020-03-16
Onvoy Communications Ltd.0.6%10,00012022-04-08
Orange Business Holdings UK Limited0.6%10,00012021-05-06
Pebbletree Ltd0.6%10,00012024-04-05
Planet Telecom Ltd0.6%10,00012019-10-08
SMARTVOICE LTD0.6%10,00012020-06-01
SONA BUSINESS PVT. LTD.0.6%10,00012023-03-27
SiPalto Ltd0.6%10,00012019-11-05
Spitfire Network Services Limited0.6%10,00012019-12-09
Syntec Limited0.6%10,00012019-10-18
TalkTalk Communications Limited0.6%10,00012020-01-09
Tata Communications (UK) Limited0.6%10,00012023-11-10
Telet Research (NI) Limited0.6%10,00012021-11-01
Windsor Telecom Limited0.6%10,00012019-10-14

Weekly changes for 0204

1 block changes from 19 Aug 2026 to 17 Oct 2026. Each week counts a block once.

0204 weekly changes since 19 Aug 2026
FromToChanged blocks
2026-08-192026-08-260
2026-08-262026-09-020
2026-09-022026-09-090
2026-09-092026-09-160
2026-09-162026-09-240
2026-09-242026-09-300
2026-09-302026-10-071
2026-10-072026-10-170

These numbers belong to 020 London. Methodology.

0204 source: Ofcom s1.csv, published 14 Oct 2026. Download 020 4 blocks (CSV). Contains Ofcom copyright material.

Source detail · 0204
0204 claim identifiers · release fc227d9e
ClaimValueIdentifier
allocated_numbers1550000subcode:020-4:allocated_numbers:fc227d9e:v1
allocated_records155subcode:020-4:allocated_records:fc227d9e:v1
listed_holders50subcode:020-4:listed_holders:fc227d9e:v1
area_code020subcode:020-4:area_code:fc227d9e:v1
first_digit4subcode:020-4:first_digit:fc227d9e:v1
snapshot_date14 Oct 2026subcode:020-4:snapshot_date:fc227d9e:v1