Size Comparison of the UK’s 30 Most Populous Urban Areas
In UK census terms, an urban area refers to any contiguous stretch of “irreversibly urban” land. By ONS definition, a built-up area must be at least 20 hectares (200,000 m²) in size, and any smaller gaps under 200 m are bridged and treated as part of the same built-up zone. In practice this means towns or cities that nearly touch each other form one larger urban area. For example, settlements like London and Reading will count as a single built-up area only if the green space between them shrinks below 200 m.
Using 2011 census data, the 30 most populous built-up areas in the UK (population over 100,000) are as follows. (For brevity, the table lists only total population and land area; most areas have densities around 3,000–4,500 people per km² by this definition.)
Rank | Urban Area (BUA) | Population (2011) | Area (km²) |
---|---|---|---|
1 | Greater London | 9,787,426 | 1,737.9 |
2 | Greater Manchester | 2,553,379 | 630.3 |
3 | West Midlands | 2,440,986 | 598.9 |
4 | West Yorkshire | 1,777,934 | 487.8 |
5 | Greater Glasgow | 957,620 | 368.5 |
6 | Liverpool | 864,122 | 199.6 |
7 | South Hampshire | 855,569 | 192.0 |
8 | Tyneside (Newcastle area) | 774,891 | 180.5 |
9 | Nottingham | 729,977 | 176.4 |
10 | Sheffield | 685,368 | 167.5 |
11 | Bristol | 617,280 | 144.4 |
12 | Belfast (N. Ireland) | 595,879 | 960.0 |
13 | Leicester | 508,916 | 109.4 |
14 | Edinburgh | 482,270 | 125.0 |
15 | Brighton & Hove | 474,485 | 89.4 |
16 | Bournemouth–Poole | 466,266 | 131.0 |
17 | Cardiff | 447,287 | 102.3 |
18 | Teesside (Middlesbrough) | 376,633 | 108.2 |
19 | Stoke-on-Trent | 372,775 | 103.9 |
20 | Coventry | 359,262 | 81.3 |
21 | Sunderland | 335,415 | 137.5 |
22 | Birkenhead (Wirral area) | 325,264 | 88.2 |
23 | Reading | 318,014 | 83.7 |
24 | Kingston upon Hull | 314,018 | 82.6 |
25 | Preston | 313,322 | 82.4 |
26 | Newport (S. Wales) | 306,844 | 84.2 |
27 | Swansea (S. Wales) | 300,352 | 87.6 |
28 | Southend-on-Sea | 295,310 | 71.8 |
29 | Derby | 270,468 | 64.1 |
30 | Plymouth | 260,203 | 59.7 |
The map below, created by Reddit user jesus_stalin shows these areas in geographic context. Greater London (in the southeast) clearly dwarfs the rest, with nearly 9.8 million people over ~1,738 km². Most other areas are much smaller: Manchester’s conurbation has ~2.55 M, Birmingham (West Midlands) ~2.44 M, Leeds/Bradford (West Yorkshire) ~1.78 M, etc.

For perspective, London’s built-up area had about 5,630 people per km² in 2011. That is actually quite high by world-city standards. Tokyo–Yokohama (37.8 M people, 8,775 km²) averaged roughly 4,300/km². Paris’s urban area (~11.1 M, 2,854 km²) is about 3,900/km². By contrast, sprawling American metros are much less dense: New York’s 2011 built-up area (~21.4 M, 11,344 km²) works out to only 1,900/km², and Los Angeles (~15.6 M, 6,918 km²) about 2,250/km². In other words, London’s urban core is actually denser than Tokyo or Paris, and far denser than New York or LA – even though its total population is smaller than Tokyo’s.
What do you think? Drop a comment below to share your thoughts on Britain’s biggest cities and how they compare globally.