SY20 postcode district
SY20 holds 421 live postcodes around Machynlleth, in Powys, Gwynedd, Ceredigion.
Towns and villages with their centre in SY20
| # | Place | County / council | Population |
|---|---|---|---|
| 1 | Machynlleth | Sir Powys | 2,235 |
| 2 | Upper Corris | Gwynedd | 200 |
Wards
| Name | Share of postcodes |
|---|---|
| Glantwymyn | 33% |
| Corris a Mawddwy | 28% |
| Machynlleth | 24% |
| Ceulan a Maesmawr | 9% |
| Aberdyfi | 6% |
| Llanbrynmair | 0% |
Westminster constituencies
| Name | Share of postcodes |
|---|---|
| Montgomeryshire and Glyndwr | 57% |
| Dwyfor Meirionnydd | 34% |
| Ceredigion Preseli | 9% |
Deprivation
The middle postcode here sits in decile 5 of the Welsh Index of Multiple Deprivation, Wales's own separate index, where decile 1 is the most deprived tenth of neighbourhoods and 10 the least. 0% of this district's postcodes sit in the most deprived three deciles, 0% in the least deprived three.
Deprivation deciles describe the LSOA neighbourhood each postcode sits in, weighted by postcodes rather than by people, because the postcode file carries no population. A district where the deprived neighbourhoods are densely populated will read better here than it would per resident.
Neighbouring districts in the SY area
SY1 · SY2 · SY3 · SY4 · SY5 · SY6 · SY7 · SY8 · SY9 · SY10 · SY11 · SY12 · SY13 · SY14 · SY15 · SY16 · SY17 · SY18 · SY19 · SY21 · SY22 · SY23 · SY24 · SY25 · SY99
Contains OS data © Crown copyright and database right 2026. Contains Royal Mail data © Royal Mail copyright and database right 2026. Source: Office for National Statistics licensed under the Open Government Licence v3.0. Postcode data is the ONS Postcode Directory, August 2026 edition; counts are live postcodes with a usable location. Northern Ireland postcodes carry a separate licence and are not included; Scotland joins when the site's Scottish coverage does.