WD18 postcode district

Postcodes and sectors

714 of the district's 1,444 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 51.64906, -0.41460, which locates the district, not a building.

Companies registered in WD18

Companies House lists 3,960 companies with a registered office in WD18; 533 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 WD18

• Hertfordshire
• Eastern
• Watford
• Three Rivers
• Rickmansworth

Roads filed under WD18

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.

• Addiscombe Road
• Alwin Place
• Argyle Court
• Ascot Road
• Aynho Street
• Banbury Street
• Barclay Close
• Basildon Close
• Beggars Bush Lane
• Belgrave Avenue
• Benskin Road
• Bentine Lane
• Blackmoor Lane
• Blanchard Drive
• Bramleas
• Brightwell Road
• Burton Avenue
• Byewaters
• Cambridge Road
• Cannon Road
• Caractacus Cottage View
• Caractacus Green
• Cardiff Road
• Cassiobridge Road
• Cassiobury Park Avenue
• Cassio Place
• Cassio Road
• Caxton Way
• Chaffinch Lane
• Charlock Way
• Chenies Way
• Cherrydale
• Chesham Way
• Chester Road
• Chestnut Court
• Chiltern Close
• Christie Court
• Church Street
• Clark Mews
• Clifton Road
• Clyston Road
• Combe Road
• Court View
• Croxley View
• Crusader Way
• Deakin Close
• Deckle Avenue
• Dumas Way
• Durban Road East
• Durban Road West
• Dwight Road
• Ebury Way
• Elfrida Road
• Epsom Road
• Etchers Avenue
• Euston Avenue
• Evensyde
• Exchange Road
• Explorer Drive
• Faraday Close

Check an address in WD18

Check an address in WD18

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

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=WD18" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about WD18

What does a WD18 postcode tell you?

That the address lies in the WD18 district of the WD (Watford) postcode area, and the place OS Open Names most often lists first for its postcodes is Watford. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 714 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 WD18

• WD171.8 km
• WD192.6 km
• WD243.0 km
• WD233.9 km
• HA64.2 km
• WD254.6 km
• WD34.7 km
• WD56.0 km
• HA56.3 km
• WD47.0 km
• HA78.3 km
• WD78.4 km
• Every district
• How a British address is written
• Check any address

distance between the districts' centroids