What does an S99 postcode tell you?

That the address lies in the S99 district of the S (Sheffield) postcode area, and the place OS Open Names most often lists first for its postcodes is Sheffield. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 35 live postcodes.

S99 postcode district

S99, in the S (Sheffield) postcode area, has 35 live and 8 terminated postcodes in the ONS Postcode Directory of August 2026, and OS Open Names files no road under it.

postcode area	S (Sheffield)
live postcodes	35
terminated postcodes	8
sectors	3
roads listed	0
centroid	53.40426, -1.43104
directory release	2026-08

Postcodes and sectors

35 of the district's 43 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 53.40426, -1.43104, which locates the district, not a building.

sector	live	terminated
S99 1	23	2
S99 2	10	4
S99 3	2	2

Places OS Open Names lists for S99

Sheffield
Yorkshire and the Humber

Roads filed under S99

OS Open Names files no road under S99, so a street here cannot be confirmed from the register and the lookup answers about the postcode alone.

Check an address in S99

Common questions about S99

What does an S99 postcode tell you?: That the address lies in the S99 district of the S (Sheffield) postcode area, and the place OS Open Names most often lists first for its postcodes is Sheffield. The district alone does not place a street: the inward half of the full postcode narrows the address to one of the district's 35 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 S99

S980.0 km
S960.5 km
S91.1 km
S41.3 km
S952.7 km
S52.9 km
S33.4 km
S13.8 km
S24.0 km
S615.0 km
S605.3 km
S135.4 km
Every district
How a British address is written
Check any address

distance between the districts' centroids

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