SS postcode district map, Southend-on-Sea
Supplier statuses last checked .
The SS postcode area covers 19 districts and 11,987 live postcodes, from SS0 to SS99. It is centred on Southend-on-Sea and also covers Basildon, Rayleigh, Canvey Island, Wickford and Stanford-le-Hope.
Districts here average 631 postcodes.
Where the SS districts sit
2 districts are plotted without a label where labels would overlap; every one is in the table below.
Where SS sits
It falls across Essex, Southend-on-Sea and Thurrock.
Water supply across SS
All 19 SS districts are supplied by Anglian Water. That makes SS simple in a way many areas are not: one company, one set of rules, one status to check.
Anglian Water has a hosepipe ban in force from 11 July 2026, covering the whole of SS.
The shape of the SS area
The districts are wildly uneven: SS7 holds 1,120 postcodes around Rayleigh and SS22 holds 3, a ratio of about 373 to one. They divide into 72 sectors.
The numbering is not continuous. SS runs up to 99 but has only 19 districts, so 81 numbers are unused:.
Several districts share a settlement, which is a common source of confusion when a form rejects an address: SS0, SS1, SS2, SS3, SS9, SS22 and SS99 all point at Southend-on-Sea, SS13, SS14, SS15 and SS16 all point at Basildon and SS5, SS6 and SS7 all point at Rayleigh.
What borders SS
SS sits next to CM (Chelmsford) to the north west, RM (Chigwell) to the west, ME (Rochester) to the south, DA (Dartford) to the south west and IG (Chigwell) to the west.
Its neighbours run in 4 different directions, so SS is landlocked by other postcode areas on most sides.
SS districts, settlements and water supply
Principal settlement is the town or city each district sits in or nearest to, derived from OS Open Names. It is not the Royal Mail post town, which is licensed data and not published openly. Status is resolved live from each company’s own notice.
Water hardness in SS
No water company covering SS publishes hardness figures as open data. The gap is named per district below so you know who to ask.
| District | Hardness | As published | Supply zone | Published by |
|---|---|---|---|---|
| SS0 | Not published by Anglian Water. Check with your supplier. | |||
| SS1 | Not published by Anglian Water. Check with your supplier. | |||
| SS2 | Not published by Anglian Water. Check with your supplier. | |||
| SS3 | Not published by Anglian Water. Check with your supplier. | |||
| SS4 | Not published by Anglian Water. Check with your supplier. | |||
| SS5 | Not published by Anglian Water. Check with your supplier. | |||
| SS6 | Not published by Anglian Water. Check with your supplier. | |||
| SS7 | Not published by Anglian Water. Check with your supplier. | |||
| SS8 | Not published by Anglian Water. Check with your supplier. | |||
| SS9 | Not published by Anglian Water. Check with your supplier. | |||
| SS11 | Not published by Anglian Water. Check with your supplier. | |||
| SS12 | Not published by Anglian Water. Check with your supplier. | |||
| SS13 | Not published by Anglian Water. Check with your supplier. | |||
| SS14 | Not published by Anglian Water. Check with your supplier. | |||
| SS15 | Not published by Anglian Water. Check with your supplier. | |||
| SS16 | Not published by Anglian Water. Check with your supplier. | |||
| SS17 | Not published by Anglian Water. Check with your supplier. | |||
| SS22 | Not published by Anglian Water. Check with your supplier. | |||
| SS99 | Not published by Anglian Water. Check with your supplier. | |||
Hardness is published per census area, not per postcode, so these figures characterise a district rather than measuring one address. They are a scale and taste matter, not a safety one. Hardness data version wessex-water@2022-2025+yorkshire-water@2026.
Download the SS data
No signup, no email wall. GeoJSON carries the district points, the supplier and the live status, so it can be dropped straight into a map.
District positions are averaged postcode centroids from OS Code-Point Open. They show roughly where a district sits, not where its boundary runs, and are not legal boundaries.
Frequently asked questions
How many postcode districts are in the SS area?
There are 19 SS postcode districts, running from SS0 to SS99, and they contain 11,987 live postcodes across 72 sectors.
What towns does the SS postcode area cover?
SS covers Southend-on-Sea, Basildon, Rayleigh, Canvey Island, Wickford and Stanford-le-Hope. The area takes its name from Southend-on-Sea, and each district is listed with its settlement in the table on this page.
Which water company supplies SS postcodes?
Anglian Water supplies all 19 SS districts. Supply boundaries follow the pipe network rather than postcode geography, so confirm against your water bill if you are near the edge of the area.
Why do SS0 and SS1 both say Southend-on-Sea?
SS0, SS1, SS2, SS3, SS9, SS22 and SS99 all serve Southend-on-Sea, covering different parts of it. A single town routinely needs more than one postcode district once it passes a few thousand delivery points, so this is normal rather than an error in an address.
Can I download a free SS postcode map?
Yes. This page offers the SS districts as GeoJSON, CSV and SVG, free and with no signup or email address required. The GeoJSON carries each district's position, its water company and its current restriction status, so it can be dropped straight into a mapping tool.
Why is the SS area called Southend-on-Sea when it covers Rayleigh?
SS takes its letters from Southend-on-Sea, where the sorting office that served the area was based when the code was allocated. Rayleigh is the largest settlement in the area today, in SS7, but the area code follows the historic sorting geography rather than current population.
Which councils cover the SS postcode area?
SS reaches into Essex, Southend-on-Sea and Thurrock. A postcode area is not a council area: they were drawn for different purposes and a single district can sit across a council boundary, so your postcode does not tell you which authority you pay.