HP18 postcode district

Postcodes and sectors

695 of the district's 773 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 51.81998, -0.96797, which locates the district, not a building.

Companies registered in HP18

Companies House lists 2,056 companies with a registered office in HP18; 392 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 HP18

• South East
• Buckinghamshire
• Aylesbury
• Long Crendon
• Waddesdon
• Oakley
• Brill
• Chearsley
• Grendon Underwood
• Cuddington
• Edgcott
• Ickford
• Ludgershall
• Shabbington
• Worminghall
• Westcott
• Oxfordshire
• Chilton
• Ashendon
• Dorton
• Cherwell
• Nether Winchendon
• Lower Winchendon
• Upper Winchendon

Roads filed under HP18

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.

• Abbot Ridge
• Alderman Drive
• Alma Street
• Amber Close
• Amorosa Gardens
• Anstey Close
• Apollo Close
• Arch Grove
• Arnott's Yd
• Ashendon Road
• Ashfield Rise
• Ashmead Street
• Auralia Close
• Avalon Street
• Avenue A
• Avenue B
• Avenue C
• Avenue D
• Averdal Drive
• Aylesbury Road
• Baker Street
• Bakery Close
• Banks Yard
• Barland Way
• Barrack Hill
• Beeley Street
• Benton Mews
• Bernard's Close
• Bernard Close
• Bernewode Close
• Berryfields
• Bicester Road
• Bilwell
• Bishops Way
• Blackgrove Road
• Blanes Close
• Blue Rock Drive
• Bonnersfield
• Bottom Orchard
• Braddons Furlong
• Bradley Close
• Braeburn Road
• Brae Hill
• Brae Hill Close
• Bramley Road
• Brandy Street
• Breedon Drive
• Bridge Road
• Bridgeway
• Brill Road
• Brokend
• Brook Close
• Brookside
• Buckingham Road
• Bulls Lane
• Burnham Road
• Burns Close
• Burt's Lane
• Calville Gardens
• Cameo Court

Check an address in HP18

Check an address in HP18

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

curl "https://spaw.co/api/v1/address/streets?country=GB&postal_code=HP18" \
  -H "Authorization: Bearer $SPAW_KEY"

Common questions about HP18

What does an HP18 postcode tell you?

That the address lies in the HP18 district of the HP (Hemel Hempstead) postcode area, and the place OS Open Names most often lists first for its postcodes is Aylesbury. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 695 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 HP18

• HP177.4 km
• OX99.2 km
• HP199.6 km
• HP2011.1 km
• HP2111.3 km
• OX3913.6 km
• OX3313.7 km
• HP2213.7 km
• HP2714.4 km
• OX2615.7 km
• OX4417.3 km
• MK1817.6 km
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distance between the districts' centroids