SL
Postcode areaPostcode area named after Slough, with 12 districts.
Approximate outline worked out by Open Index from the ONS Postcode Directory: the outline joins its districts’ outlines, each made of the census output areas that hold most of the district’s postcodes.
Radon Affected Area by postcode area
Worked out by Open Index · 2022
About 41% of people in SL live in a 1 km square that the radon atlas marks as a radon Affected Area.
How SL compares
Each dot is a postcode area. The black line marks the middle one.
Every postcode area ranked: median sale price, population, people in radon affected area squares and gigabit broadband coverage.
Is SL safe? What police records show
In the 12 months to August 2026, police recorded crimes and anti-social behaviour in SL at a rate of 77.9 per 1,000 people.
In August 2026 alone, 2,920 cases of crime and anti-social behaviour were recorded in SL.
In the 12 months to August 2026, the most common types were violence and sexual offences (12,198), other crime (6,781) and anti-social behaviour (3,496).
A year earlier, the recorded crime rate in SL was 76.5 per 1,000 people.
Worked out by Open Index from police.uk crime records and ONS and NISRA population estimates.
Rates are per resident, so places that many people work in or visit, such as Westminster, the City of London and other city centres, have far higher rates than their residents alone would suggest.
Postcode districts in SL
| Name | People (census) | Median sale price | Recorded crime per 1,000 |
|---|---|---|---|
| SL0Iver Heath, Richings Park | 11,670 | £557,500 | 68.8 per 1,000 |
| SL1Slough, Cippenham | 79,692 | £395,931 | 123.4 per 1,000 |
| SL2Slough, Farnham Royal | 58,969 | £432,000 | 72.1 per 1,000 |
| SL3Slough, Langley | 50,366 | £453,000 | 84.7 per 1,000 |
| SL4Windsor, Dedworth | 45,871 | £517,250 | 83.8 per 1,000 |
| SL5North Ascot, Sunninghill | 24,579 | £650,000 | 42.5 per 1,000 |
| SL6Maidenhead, Boyn Hill | 83,062 | £510,000 | 59.0 per 1,000 |
| SL7Marlow | 21,220 | £650,000 | 51.7 per 1,000 |
| SL8Bourne End, Cores End | 6,817 | £561,250 | 39.6 per 1,000 |
| SL9Chalfont St Peter, Gerrards Cross | 22,256 | £867,500 | 46.5 per 1,000 |
| SL60Maidenhead | 339 | No figure | 115.6 per 1,000 |
| SL95Sutton | 408 | No figure | 132.6 per 1,000 |
SL in brief
The SL postcode area, named after Slough, has 12 postcode districts.
The median price paid for a home in SL was £510,000 in 2025.
SL had 405,249 usual residents at the census.
About 41% of people in SL live in a 1 km square that the radon atlas marks as a radon Affected Area.
In SL, 89.0% of homes and businesses could get gigabit-capable broadband in January 2026.