Greater London tops the ranking, with 8,805,417 residents, ahead of West Midlands and Greater Manchester. The full ranking is below, each entry linked to its page.

# County Population
1 Greater London 8,805,417
2 West Midlands 2,913,889
3 Greater Manchester 2,864,829
4 West Yorkshire 2,327,972
5 Essex 1,879,394
6 Hampshire 1,863,451
7 Kent 1,852,764
8 Lancashire 1,535,323
9 Merseyside 1,418,883
10 South Yorkshire 1,376,161
11 Devon 1,216,729
12 Surrey 1,194,814
13 Hertfordshire 1,182,100
14 Nottinghamshire 1,145,226
15 North Yorkshire 1,140,932
16 Staffordshire 1,138,148
17 Tyne and Wear 1,131,809
18 Cheshire 1,093,983
19 Lincolnshire 1,082,550
20 Leicestershire 1,081,898
21 Derbyshire 1,057,684
22 Somerset 983,434
23 Berkshire 945,736
24 Gloucestershire 936,637
25 Norfolk 914,439
26 County Durham 914,238
27 Cambridgeshire 899,729
28 West Sussex 884,209
29 Buckinghamshire 846,864
30 East Sussex 824,106
31 Northamptonshire 785,298
32 Dorset 775,383
33 Suffolk 755,855
34 Wiltshire 739,392
35 Oxfordshire 724,367
36 Bedfordshire 706,591
37 Glasgow City 617,149
38 Worcestershire 607,667
39 East Riding of Yorkshire 599,058
40 Warwickshire 595,446
41 Cornwall 570,757
42 City of Edinburgh 514,073
43 Shropshire 502,842
44 Cumbria 501,093
45 Bristol 475,648
46 Fife 372,984
47 Cardiff 363,589
48 North Lanarkshire 344,263
49 South Lanarkshire 328,758
50 Northumberland 318,641
51 Aberdeenshire 256,371
52 Swansea 240,159
53 Rhondda Cynon Taf 233,945
54 Aberdeen City 231,144
55 Highland 229,318
56 Herefordshire 187,551
57 Carmarthenshire 185,368
58 Renfrewshire 185,061
59 West Lothian 180,252
60 Caerphilly 178,349
61 Newport 160,728
62 Falkirk 158,255
63 Flintshire 157,266
64 Perth and Kinross 151,271
65 Dundee City 151,073
66 Bridgend 147,575
67 Dumfries and Galloway 145,892
68 Neath Port Talbot 143,741
69 Isle of Wight 140,460
70 North Ayrshire 133,991
71 Wrexham 133,476
72 The Vale of Glamorgan 131,305
73 Powys 129,961
74 Pembrokeshire 123,443
75 Gwynedd 118,529
76 East Ayrshire 118,455
77 Scottish Borders 116,207
78 Conwy 113,823
79 East Lothian 113,073
80 South Ayrshire 113,064
81 Angus 111,522
82 East Dunbartonshire 107,164
83 East Renfrewshire 96,750
84 Denbighshire 96,586
85 Midlothian 96,532
86 Moray 93,691
87 Stirling 92,390
88 Torfaen 92,056
89 Monmouthshire 91,434
90 West Dunbartonshire 88,383
91 Argyll and Bute 85,698
92 Inverclyde 77,652
93 Ceredigion 71,411
94 Isle of Anglesey 68,852
95 Blaenau Gwent 65,205
96 Merthyr Tydfil 58,753
97 Clackmannanshire 51,026
98 Rutland 44,041
99 Na h-Eileanan an Iar 26,135
100 Shetland Islands 22,978
101 Orkney Islands 21,961

Source: ONS Census 2021. Compiled by Postcodes UK.

Frequently asked questions

Which is the most populous county in the UK?

Greater London tops the list, with 8,805,417 residents, followed by West Midlands and Greater Manchester.

How is this ranking measured?

This ranking is based on ONS Census 2021. It covers the ceremonial counties of England and the council and principal areas of Scotland and Wales.