This is a list of settlements in Northamptonshire ordered by population based on the results of the 2011 census. In 2011, there were 18 settlements with 5,000 or more inhabitants in Northamptonshire. The next United Kingdom census will take place in 2021.
| Rank | Town | Population | Borough/district | Notes | |
|---|---|---|---|---|---|
| 1 | 243,511 (2021) | ||||
| 2 | 68,164 (2021)[1] | ||||
| 3 | 63,144 (2021) | North Northamptonshire | |||
| 4 | 54,412 (2021) | North Northamptonshire | |||
| 5 | 31,690 (2021) | North Northamptonshire | |||
| 6 | 27,786 (2021) | West Northamptonshire | |||
| 7 | 16,195 (2021) | West Northamptonshire | |||
| 8 | 11,910 (2021) | North Northamptonshire | |||
| 9 | 11,331 (2021) | West Northamptonshire | |||
| 10 | 10,444 (2021) | North Northamptonshire | Part of Kettering's urban area | ||
| 11 | 10,233 (2021) | North Northamptonshire | |||
| 12 | 9,325 (2021) | North Northamptonshire | |||
| 13 | 8,827 (2021) | North Northamptonshire | Part of Rushden's urban area | ||
| 14 | 8,624 (2021) | North Northamptonshire | |||
| 15 | 7,238 (2021) | North Northamptonshire | |||
| 16 | 6,254 (2021) | North Northamptonshire | |||
| 17 | 6,069 (2021) | North Northamptonshire | |||
| 18 | 5,766 (2021) | West Northamptonshire |