DN postcode district map, Doncaster
Supplier statuses last checked .
The DN postcode area covers 32 districts and 22,343 live postcodes, from DN1 to DN41. It is centred on Doncaster and also covers Grimsby, Scunthorpe, Goole, Cleethorpes and Gainsborough.
Districts here average 698 postcodes.
Where the DN districts sit
9 districts are plotted without a label where labels would overlap; every one is in the table below.
Where DN sits
It is administratively fragmented, reaching into Doncaster, North Lincolnshire, North East Lincolnshire and Lincolnshire and 3 other authorities.
Water supply across DN
All 32 DN districts are supplied by Yorkshire Water, which is notable at this size: an area with this many districts usually crosses at least one supply boundary, and this one does not.
No hosepipe ban currently applies anywhere in DN.
The shape of the DN area
DN14 is the largest district with 1,693 postcodes around Goole, and DN38 the smallest with 105. The area divides into 116 postcode sectors.
The numbering is not continuous. DN runs up to 41 but has only 32 districts, so 9 numbers are unused:.
Several districts share a settlement, which is a common source of confusion when a form rejects an address: DN31, DN32, DN33, DN34 and DN37 all point at Grimsby, DN1, DN2, DN3 and DN4 all point at Doncaster and DN39, DN40 and DN41 all point at Immingham.
What borders DN
DN sits next to LN (Lincoln) to the south east, HU (Kingston upon Hull) to the north east, S (Sheffield) to the west, NG (Nottingham) to the south and WF (Wakefield) to the west.
Its neighbours run in 4 different directions, so DN is landlocked by other postcode areas on most sides.
DN districts, settlements and water supply
| District | Principal settlement | Water company | Hosepipe ban status |
|---|---|---|---|
| DN1 | Doncaster | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN2 | Doncaster | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN3 | Doncaster | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN4 | Doncaster | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN5 | Bentley | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN6 | Adwick le Street | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN7 | Thorne | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN8 | Thorne | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN9 | Epworth | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN10 | Bawtry | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN11 | Tickhill | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN12 | Conisbrough | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN14 | Goole | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN15 | Scunthorpe | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN16 | Scunthorpe | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN17 | Crowle | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN18 | Barton-upon-Humber | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN19 | Barton-upon-Humber | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN20 | Brigg | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN21 | Gainsborough | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN22 | Retford | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN31 | Grimsby | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN32 | Grimsby | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN33 | Grimsby | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN34 | Grimsby | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN35 | Cleethorpes | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN36 | Cleethorpes | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN37 | Grimsby | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN38 | Brigg | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN39 | Immingham | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN40 | Immingham | Yorkshire Water / Severn Trent | Depends on your supplier |
| DN41 | Immingham | Yorkshire Water / Severn Trent | Depends on your supplier |
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 DN
Figures are in milligrams per litre as calcium carbonate, the unit UK water companies report in. 12 of 32 districts have a published figure.
| District | Hardness | As published | Supply zone | Published by |
|---|---|---|---|---|
| DN1 | 254.7 mg/l That is hard on the water industry scale. | 254.7 mg/l as CaCO₃ | E01007647 | Yorkshire Water 2026 edition |
| DN2 | 248.2–257.2 mg/l varies across this district | 251.7 mg/l as CaCO₃ | E01007569, E01007652, E01007654 | Yorkshire Water 2026 edition |
| DN3 | 244.2–254.7 mg/l varies across this district | 251.6 mg/l as CaCO₃ | E01007477, E01007479, E01007480, E01007631 +1 more | Yorkshire Water 2026 edition |
| DN4 | 267.2 mg/l That is hard on the water industry scale. | 267.2 mg/l as CaCO₃ | E01007496, E01007534 | Yorkshire Water 2026 edition |
| DN5 | 271.8 mg/l That is hard on the water industry scale. | 271.8 mg/l as CaCO₃ | E01007509, E01007513, E01007584, E01007588 +2 more | Yorkshire Water 2026 edition |
| DN6 | 266.4 mg/l That is hard on the water industry scale. | 266.4 mg/l as CaCO₃ | E01007470, E01007472, E01007488 | Yorkshire Water 2026 edition |
| DN7 | 260.5 mg/l That is hard on the water industry scale. | 260.5 mg/l as CaCO₃ | E01007556, E01007625, E01007629 | Yorkshire Water 2026 edition |
| DN8 | 244–252.2 mg/l varies across this district | 248.2 mg/l as CaCO₃ | E01007639, E01007640, E01013249 | Yorkshire Water 2026 edition |
| DN9 | 249.7–254.7 mg/l varies across this district | 252.2 mg/l as CaCO₃ | E01013244, E01013250 | Yorkshire Water 2026 edition |
| DN10 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN11 | 209.5–299.7 mg/l varies across this district | 244 mg/l as CaCO₃ | E01007593, E01007612, E01007615 | Yorkshire Water 2026 edition |
| DN12 | 268.3 mg/l That is hard on the water industry scale. | 268.3 mg/l as CaCO₃ | E01007536, E01007538, E01007552 | Yorkshire Water 2026 edition |
| DN14 | 279.1 mg/l That is hard on the water industry scale. | 279.1 mg/l as CaCO₃ | E01012993, E01012994, E01012996 | Yorkshire Water 2026 edition |
| DN15 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN16 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN17 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN18 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN19 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN20 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN21 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN22 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN31 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN32 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN33 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN34 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN35 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN36 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN37 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN38 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN39 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN40 | Not published by Yorkshire Water. Check with your supplier. | |||
| DN41 | Not published by Yorkshire Water. Check with your supplier. | |||
Descriptions such as very soft, soft, moderately hard, hard, very hard are the water industry scale: very soft below 75, soft 75–125, moderately hard 125–250, hard 250–375, very hard above 375 mg/l. Your supplier may use a different scale for the same number.
Contains Yorkshire Water drinking water quality data, via Stream, licensed under CC BY 4.0. Edition 2026, published 1 January 2026. Yorkshire Water publishes this as mg/l without naming the species. We read it as calcium carbonate because the determinand is Hardness total and the dataset contains no calcium determinand. Evidence: determinand "Hardness total"; DWI code "HARD T"; no calcium determinand published in the dataset.
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 DN 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 DN area?
There are 32 DN postcode districts, running from DN1 to DN41, and they contain 22,343 live postcodes across 116 sectors.
What towns does the DN postcode area cover?
DN covers Doncaster, Grimsby, Scunthorpe, Goole, Cleethorpes and Gainsborough. The area takes its name from Doncaster, and each district is listed with its settlement in the table on this page.
Which water company supplies DN postcodes?
Yorkshire Water supplies all 32 DN 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 DN31 and DN32 both say Grimsby?
DN31, DN32, DN33, DN34 and DN37 all serve Grimsby, 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 DN postcode map?
Yes. This page offers the DN 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 DN area called Doncaster when it covers Goole?
DN takes its letters from Doncaster, where the sorting office that served the area was based when the code was allocated. Goole is the largest settlement in the area today, in DN14, but the area code follows the historic sorting geography rather than current population.
Which councils cover the DN postcode area?
DN reaches into Doncaster, North Lincolnshire, North East Lincolnshire, Lincolnshire, Nottinghamshire, North Yorkshire and East Riding of Yorkshire. 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.