Planes overhead in SM4
Merton and Sutton, London. All 581 of its postcodes measured, January to August 2026.
From Heathrow
Planes land and take off into the wind, so the weather decides which way Heathrow flies, and that decides how many pass over SM4. Across its postcodes, January to August 2026:
- On a day it flies west (56% of days): up to 59 a day; of its 581 postcodes, 492 at 10 to 99, 89 under 10
- On a day it flies both ways (15% of days): up to 54 a day; of its 581 postcodes, 534 at 10 to 99, 47 under 10
- On a day it flies east (29% of days): up to 107 a day; of its 581 postcodes, 1 at 100+, 16 at 10 to 99, 51 on an edge, 513 under 10
The table counts the postcodes of each sector by how many planes pass over them a day: 100 or more, 10 to 99, or under 10.
| Sector | Flying west56% of days | Both ways15% of days | Flying east29% of days |
|---|---|---|---|
| SM4 4178 postcodes | 141 at 10 to 9937 under 10 | 132 at 10 to 9946 under 10 | 6 on an edge172 under 10 |
| SM4 5165 postcodes | 135 at 10 to 9930 under 10 | 164 at 10 to 991 under 10 | 1 at 100+16 at 10 to 9923 on an edge125 under 10 |
| SM4 6211 postcodes | 211 at 10 to 99 | 211 at 10 to 99 | 211 under 10 |
| SM4 927 postcodes | 5 at 10 to 9922 under 10 | 27 at 10 to 99 | 22 on an edge5 under 10 |
On an edge: the postcode is on the edge of a flight path, where a few metres decide whether a plane counts as overhead, and the fewest and the most within 100 m of it fall in different bands.
1 of its postcodes have a position ONS estimates, so their figures may be for a spot a few hundred metres away.
What counts as overhead
Overhead means more than halfway up the sky (48.5 degrees or more) and below 7,000 ft, the CAA's definition of an overflight (CAP 1498). A day counts as one way when 80% of its flights used that way.
Near SM4
SM3 SW20 SM1 CR4 KT4 SM5 SW19 KT3
The councils
Where these figures come from
Counted from community flight tracking, checked against the CAA's monthly totals for Heathrow. Flight tracks: adsb.lol (ODbL 1.0); Weather at each airport: Iowa Environmental Mesonet; Ground heights: Contains OS data © Crown copyright and database right; Postcode positions: ONS National Statistics Postcode Lookup (OGL). Licence: Open Database License (ODbL) 1.0.