What does a SA11 postcode tell you?

That the address lies in the SA11 district of the SA (Swansea) postcode area, which the directory places around Wales. The inward half of the full postcode narrows it to a street or a building; the district alone does not, and an address written with a district and no inward half cannot be checked against the register.

Does a street listed here mean an address on it exists?

It means OS Open Names lists a road of that name under the district, which is what the address lookup answers as a street-level match. It says nothing about any building on it: Great Britain publishes no open register of buildings, so the lookup answers exists: null there and confirms the street alone.

Who lives at these postcodes?

Nobody on this page. A postcode directory says whether a code is in use, never who is there, and a streets register lists roads, not occupants. The address lookup carries no field about a person and never will.

SA11 postcode district

What the public directories installed here say about the SA11 postcode district: how many of its postcodes are in use, the places OS Open Names lists for them, the streets it files under the district and the district's centroid. Counted from the national postcode directory and OS Open Names on 2026-09-18, and never about who is at an address.

postcode area	SA (Swansea)
live postcodes	989
terminated postcodes	288
streets listed	608
centroid	51.67488, -3.76135
counted on	2026-09-18

Places the directory lists for SA11

OS Open Names places the district's postcodes in these settlements, boroughs, counties and regions, most often first. A town written as any of them matches the directory in an address lookup, and one written as another place in the SA area is reported but not scored.

Wales
Castell-nedd Port Talbot
Neath Port Talbot
Neath
Castell-nedd
Briton Ferry
Llansawel
Glyn-neath
Glyn-nedd
Resolfen
Resolven
Tonna
Powys
Cwmgwrach
Melincourt
Pontneddfechan
Blaengwrach
Clyne
Abergarwed
Pentreclwydau
Rhondda Cynon Taf

Postcodes in use

989 postcodes in SA11 were in use on the day of the count. A postcode directory says whether a code is in use, never who is there. 288 of its 1,277 postcodes have been terminated: a real address written with one has moved on, which is not the same thing as a typo, and the address lookup scores it rather than refusing it.

Centroid: 51.67488, -3.76135 — the mean of the live postcodes' centroids, which locates the district, not any building in it.

Streets filed under SA11

OS Open Names files 608 roads under SA11. A road is filed under one district even where it runs through several, so a street missing here may be listed under a neighbouring district — which is why the address lookup never calls a British street absent.

A465
A4109
Aberdare Road
Abermellte Court
Addison Road
Addoldy Road
Afan Valley Close
Afan Valley Road
Alder Road
Alexander Road
Alford Road
Alfred Street
Alice Street
Allister Street
Angel Square
Angel Street
Arthur Street
Ash Grove
Ashmere Drive
Aspen Way

the first 20 of 608, alphabetically

Check an address in SA11

The address checker opens on Great Britain with the district in the field: add the street, the number and the full postcode, and it answers the postcode's status, whether the street is filed under the district, and what kind of delivery point the address names.

Check an address in SA11

curl https://spaw.co/api/v1/address \
  -H "Authorization: Bearer sk_live_…" \
  -H "Content-Type: application/json" \
  -d '{"address": "10 Downing Street, London SA11 …", "country": "GB"}'

Common questions about SA11

What does a SA11 postcode tell you?: That the address lies in the SA11 district of the SA (Swansea) postcode area, which the directory places around Wales. The inward half of the full postcode narrows it to a street or a building; the district alone does not, and an address written with a district and no inward half cannot be checked against the register.
Does a street listed here mean an address on it exists?: It means OS Open Names lists a road of that name under the district, which is what the address lookup answers as a street-level match. It says nothing about any building on it: Great Britain publishes no open register of buildings, so the lookup answers exists: null there and confirms the street alone.
Who lives at these postcodes?: Nobody on this page. A postcode directory says whether a code is in use, never who is there, and a streets register lists roads, not occupants. The address lookup carries no field about a person and never will.

Where the counts come from

ons-postcode-directory · version 2026-08 · Contains ONS, OS and Royal Mail data © Crown copyright and database right 2026, Open Government Licence v3.0. Northern Ireland postcodes are excluded: their reuse needs a Land & Property Services licence.

Data synced on 2026-09-18: the newest register or postcode directory copy installed here.

Other districts in SA

Wrong result, or is it about you? If this tool said something you think is wrong, tell us and a person reads it. If Spaw is holding data about you and you never signed up here — a customer may have had your address verified, or reported that a message to it bounced — erase it yourself, confirmed by mail to that address and with no account needed.

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