What does a WD99 postcode tell you?

That the address lies in the WD99 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 21 live postcodes.

WD99 postcode district

WD99, in the WD (Watford) postcode area, has 21 live and 2 terminated postcodes in the ONS Postcode Directory of August 2026, and OS Open Names files no road under it.

postcode area	WD (Watford)
live postcodes	21
terminated postcodes	2
sectors	1
roads listed	0
centroid	51.64878, -0.42207
directory release	2026-08

Postcodes and sectors

21 of the district's 23 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 51.64878, -0.42207, which locates the district, not a building.

sector	live	terminated
WD99 1	21	2

Places OS Open Names lists for WD99

Watford
Hertfordshire
Eastern

Roads filed under WD99

OS Open Names files no road under WD99, so a street here cannot be confirmed from the register and the lookup answers about the postcode alone.

Check an address in WD99

Common questions about WD99

What does a WD99 postcode tell you?: That the address lies in the WD99 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 21 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 WD99

WD180.5 km
WD172.0 km
WD193.0 km
WD243.2 km
HA64.1 km
WD34.2 km
WD234.4 km
WD254.9 km
WD56.1 km
HA56.5 km
WD46.9 km
UB98.5 km
Every district
How a British address is written
Check any address

distance between the districts' centroids

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