CF42 postcode district

Postcodes and sectors

310 of the district's 383 postcodes are live in the ONS Postcode Directory of August 2026. A postcode directory says whether a code is in use, never who is there. The live postcodes centre on 51.66750, -3.52419, which locates the district, not a building.

Companies registered in CF42

Companies House lists 399 companies with a registered office in CF42; 93 of them at addresses shared by 25 or more companies (1 October 2026 snapshot). 25 is the count at which the address lookup reports a company cluster.

Places OS Open Names lists for CF42

• Rhondda Cynon Taf
• Wales
• Treorchy
• Treorci
• Treherbert

Roads filed under CF42

Named roads first, then numbered ones. 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. Great Britain has no open register of buildings, so a listed road never means a building on it exists.

• Abertonllwyd Street
• Adare Terrace
• Ael-y-Bryn
• Alma Street
• Baglan Street
• Barrett Street
• Blaen-y-Cwm Road
• Blaen-y-Cwm Terrace
• Blaenrhondda Road
• Brook Street
• Brynfedwen Close
• Bryn Henllan
• Bryn Heulog
• Brynhyfryd Street
• Bryn Rhedyn
• Bryn Rhodfa
• Bryn Wyndham Terrace
• Bute Street
• Bwlch-y-Clawdd Road
• Cadwgan Road
• Cardiff Place
• Cardiff Street
• Carmel Street
• Caroline Street
• Castle Street
• Castleton Avenue
• Cemetery Road
• Chapel Street
• Charles Street
• Chepstow Road
• Church Street
• Clare Road
• Clark Street
• Clifton Street
• Clos Ioan
• Clyngwyn Road
• Coldra Road
• Column Street
• Conway Road
• Corbett Street
• Crichton Street
• Cross Brook Street
• Crosswood Street
• Crown Avenue
• Crown Terrace
• Cwmsaerbren Street
• Cŵrt-Yr-Ysgol
• David Street
• Delwen Terrace
• Dilys Street
• Druids Close
• Dumfries Street
• Dunraven Court
• Dunraven Street
• Dunraven Terrace
• Dyfodwg Street
• Eileen Place
• Eleanor Street
• Emmanuel Close
• Fforch Close

Check an address in CF42

Check an address in CF42

The same road list through the API, from the outward code alone:

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=CF42" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about CF42

What does a CF42 postcode tell you?

That the address lies in the CF42 district of the CF (Cardiff) postcode area, and the place OS Open Names most often lists first for its postcodes is Treorchy. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 310 live postcodes.

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.
• os-open-names · version 2026-11-01 · Contains OS data © Crown copyright and database right 2026, Open Government Licence v3.0.
• uk-companies-house · version 2026-10-01 · Companies House free company data product, Open Government Licence v3.0

What each figure means, and what a district page never says, is set out in Reading a British postcode district page; the glossary defines a postcode district, a postcode area, a postcode directory and a street register.

Data synced on 2026-11-01: the newest version among the datasets listed above.

Districts nearest CF42

• CF413.7 km
• CF435.2 km
• CF447.2 km
• CF407.2 km
• CF3910.2 km
• CF3410.9 km
• CF4511.2 km
• CF3212.7 km
• CF4813.4 km
• CF4713.9 km
• CF3714.9 km
• CF4615.4 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids