Subsidence Risk Index
UK Subsidence Risk Index 2026
We ranked 46UK cities by BGS clay shrink-swell susceptibility — the single biggest driver of subsidence — with historic mining as a second factor. The context most buyers miss: subsidence is a dry-summer risk, and the ABI's 2022 heatwave bill hit £219m, the highest since 2006.
Headline findings
- Londonranks highest — most boroughs sit on high to very high susceptibility London Clay, the textbook UK shrink-swell geology.
- Chelmsford ranks #2 on high-susceptibility Essex London Clay, ahead of a moderate-to-high belt: Cambridge, Luton, Milton Keynes, Oxford, Peterborough, Portsmouth, Reading and Southampton on Gault, Oxford and Tertiary clays.
- In the Midlands, North and South Wales, historic coal and stone mining adds ground-stability risk even where clay susceptibility is lower.
Last updated: 24 June 2026. Editorially reviewed: 24 June 2026.
Media and citation pack
Use this subsidence dataset in a story
Journalists and property writers can cite the index freely with attribution to MyPropertyScan, the British Geological Survey and the ABI. The strongest seasonal angle is the dry-summer subsidence spike: clay soils shrink in heat, and the ABI's £219m 2022 bill was the highest since 2006.
Top local hook
Londontops the list on BGS clay susceptibility — the geology behind most dry-summer subsidence claims.
National stat
ABI: £219m expected subsidence bill for 2022 (~23,000 claims), highest since 2006.
Suggested attribution
Data source: MyPropertyScan analysis of British Geological Survey GeoSure shrink-swell data and ABI subsidence claims. Full ranking and dataset: UK Subsidence Risk Index 2026.
Tool shortcut
Check subsidence signals for a UK address in 15 seconds
BGS clay susceptibility, building age, tree context and the things to ask your surveyor.
Run a free previewHighest clay subsidence risk
Clay shrink-swell is the dominant cause of UK subsidence. These cities sit on the highest-susceptibility clays, where dry summers and mature trees do the most damage. Band is the BGS GeoSure shrink-swell rating, summarised for the city:
#1
London
Very High
#2
Chelmsford
High
#3
Cambridge
Moderate–High
#4
Luton
Moderate–High
#5
Milton Keynes
Moderate–High
#6
Oxford
Moderate–High
#7
Peterborough
Moderate–High
#8
Portsmouth
Moderate–High
Where mining adds ground-stability risk
In the coalfields and historic mining areas, ground movement from abandoned workings is a buyer issue in its own right — even where clay susceptibility is lower. A Coal Authority (CON29M) search is standard practice in these cities:
- Birmingham: Moderate clay band, significant historic mining (clay + mining).
- Bristol: Moderate clay band, significant historic mining (clay + mining).
- Coventry: Moderate clay band, significant historic mining (clay + mining).
- Derby: Moderate clay band, significant historic mining (clay + mining).
- Leicester: Moderate clay band, significant historic mining (clay + mining).
- Manchester: Moderate clay band, significant historic mining (clay + mining).
Full ranking: 46 cities
Download the dataset (CSV)Ranked by BGS clay shrink-swell band (the dominant subsidence driver); within each band, cities with significant historic mining are listed first, then alphabetically. Click a city for its local subsidence guide.
| # | City | Clay band | Mining | Primary driver |
|---|---|---|---|---|
| 1 | LondonGreater London | Very High | Limited | Clay shrink-swell |
| 2 | ChelmsfordEssex | High | Limited | Clay shrink-swell |
| 3 | CambridgeCambridgeshire | Moderate–High | Limited | Clay shrink-swell |
| 4 | LutonBedfordshire | Moderate–High | Limited | Clay shrink-swell |
| 5 | Milton KeynesBuckinghamshire | Moderate–High | Limited | Clay shrink-swell |
| 6 | OxfordOxfordshire | Moderate–High | Limited | Clay shrink-swell |
| 7 | PeterboroughCambridgeshire | Moderate–High | Limited | Clay shrink-swell |
| 8 | PortsmouthHampshire | Moderate–High | Limited | Clay shrink-swell |
| 9 | ReadingBerkshire | Moderate–High | Limited | Clay shrink-swell |
| 10 | SouthamptonHampshire | Moderate–High | Limited | Clay shrink-swell |
| 11 | BirminghamWest Midlands | Moderate | Significant | Clay + mining |
| 12 | BristolBristol | Moderate | Significant | Clay + mining |
| 13 | CoventryWest Midlands | Moderate | Significant | Clay + mining |
| 14 | DerbyDerbyshire | Moderate | Significant | Clay + mining |
| 15 | LeicesterLeicestershire | Moderate | Significant | Clay + mining |
| 16 | ManchesterGreater Manchester | Moderate | Significant | Clay + mining |
| 17 | NorwichNorfolk | Moderate | Significant | Chalk mining |
| 18 | WolverhamptonWest Midlands | Moderate | Significant | Clay + mining |
| 19 | ChichesterWest Sussex | Moderate | Limited | Clay shrink-swell |
| 20 | ElyCambridgeshire | Moderate | Limited | Peat shrinkage / clay |
| 21 | GloucesterGloucestershire | Moderate | Some | Clay shrink-swell |
| 22 | GuildfordSurrey | Moderate | Some | Clay shrink-swell |
| 23 | Kingston upon HullEast Yorkshire | Moderate | Limited | Soft alluvial ground |
| 24 | NorthamptonNorthamptonshire | Moderate | Some | Clay shrink-swell |
| 25 | ShrewsburyShropshire | Moderate | Some | Clay shrink-swell |
| 26 | WorcesterWorcestershire | Moderate | Some | Clay shrink-swell |
| 27 | YorkNorth Yorkshire | Moderate | Limited | Clay shrink-swell |
| 28 | BradfordWest Yorkshire | Low–Moderate | Significant | Historic mining |
| 29 | DoncasterSouth Yorkshire | Low–Moderate | Significant | Historic mining |
| 30 | LeedsWest Yorkshire | Low–Moderate | Significant | Historic mining |
| 31 | Newcastle upon TyneTyne and Wear | Low–Moderate | Significant | Historic mining |
| 32 | NottinghamNottinghamshire | Low–Moderate | Significant | Historic mining |
| 33 | SalfordGreater Manchester | Low–Moderate | Significant | Historic mining |
| 34 | SheffieldSouth Yorkshire | Low–Moderate | Significant | Historic mining |
| 35 | Stoke-on-TrentStaffordshire | Low–Moderate | Significant | Historic mining |
| 36 | SwanseaSouth Wales | Low–Moderate | Significant | Historic mining |
| 37 | CarlisleCumbria | Low–Moderate | Limited | Soft alluvial ground |
| 38 | HerefordHerefordshire | Low–Moderate | Limited | Clay shrink-swell |
| 39 | LincolnLincolnshire | Low–Moderate | Limited | Clay shrink-swell |
| 40 | LiverpoolMerseyside | Low–Moderate | Some | Clay shrink-swell |
| 41 | SunderlandTyne and Wear | Low | Significant | Historic mining |
| 42 | AberdeenAberdeenshire (Scotland) | Low | Limited | Granite (low risk) |
| 43 | BathSomerset | Low | Some | Limestone / slope instability |
| 44 | ExeterDevon | Low | Some | Sandstone (low risk) |
| 45 | PlymouthDevon | Low | Some | Limestone karst / mining |
| 46 | WinchesterHampshire | Low | Limited | Chalk / soft ground |
Method and sources
Cities are ranked by their British Geological Survey GeoSure clay shrink-swell susceptibility band — the dominant cause of UK subsidence — summarised for the built-up area from Low to Very High. Historic mining ground-stability (coal, stone, chalk or ironstone workings) is shown as a second factor and breaks ties. Bands are categorical, not claim counts: a single property's risk still depends on its soil, trees, drains and foundations, so always confirm at address level.
Sources: British Geological Survey (GeoSure shrink-swell) and the Association of British Insurers (subsidence claims, 2022–2023). City-level summaries by MyPropertyScan; free to cite with attribution to MyPropertyScan, BGS and the ABI.
Check a specific address
A city-level band is a starting point, not an address verdict. Run the postcode through the subsidence risk postcode checker and read the subsidence risk buying guide before you make an offer.
Run the check
Check subsidence signals for a UK address in 15 seconds
BGS clay susceptibility, building age, tree context and the things to ask your surveyor.
Run a free previewFrequently asked questions
Which UK cities have the highest subsidence risk?
On BGS clay shrink-swell susceptibility — the dominant cause of UK subsidence — London ranks highest, sitting on high to very high susceptibility London Clay. Chelmsford is next, on high-susceptibility Essex London Clay, followed by a moderate-to-high belt: Cambridge, Luton, Milton Keynes, Oxford, Peterborough, Portsmouth, Reading and Southampton, on Gault, Oxford and Tertiary clays. The ABI's 2022 figures show subsidence claims spike in dry summers, when these clays shrink.
What causes subsidence in UK homes?
The largest single cause is clay shrink-swell: high-plasticity clays shrink in dry summers and swell when wet, moving foundations. Mature trees close to the building accelerate it by drawing moisture from the clay. Other causes include leaking drains washing out soil, and historic mine workings — coal, stone, chalk or ironstone — which matter even where clay risk is low.
How bad is UK subsidence in a hot summer?
The Association of British Insurers (ABI) reported an expected £219 million subsidence bill for 2022 — the highest since 2006 — after the record 40.3°C July heatwave, from around 23,000 claims. Claims and payouts continued into 2023 as cases were monitored and settled. Subsidence is fundamentally a dry-summer risk on clay soils.
How do I check subsidence risk for a specific postcode?
Start with the BGS GeoSure shrink-swell band for the postcode, then check for mature trees near the building and the property's insurance claim history. For an instant BGS clay summary, use the MyPropertyScan subsidence risk postcode checker; the city guides cover the local mining history, and your conveyancer's environmental search confirms mining and ground-stability detail before exchange.
Keep going
Related guides
- Subsidence risk when buying a house , viewing red flags, mortgage and insurance impact, and the negotiation script.
- UK Property Flood Risk Index , the companion ranking of cities by flood exposure.
- House buying checklist , every pre-offer check in one place.
Editorial review
Reviewed by the MyPropertyScan editorial team. Editorial owner: BiteRight Ltd, operator of MyPropertyScan. We review buyer guides against UK public property datasets, RICS survey wording, lender requirements, and common buyer questions.
Pages are updated when source coverage, property-risk guidance, survey cost assumptions, or product checks materially change. Methodology and dataset limitations are explained on the MyPropertyScan methodology page.
Sources used
We use UK public and specialist sources where they are available. Public datasets can be incomplete, delayed, or missing for some addresses. Treat them as a starting point, not as a replacement for professional advice.
Source standard: preference goes to official government datasets, statutory bodies, professional standards, and primary dataset publishers. We cite the source family on the page and explain coverage limits rather than filling gaps with unsupported estimates.
- Check this with: Environment Agency long-term flood risk mapOfficial flood-risk service for England, including river, sea, surface water, reservoir and groundwater where available.
- Data source: HM Land Registry Price Paid DataRegistered residential sale prices for England and Wales.
- Official register: Energy Performance Certificate RegisterPublic EPC certificate lookup for an address, postcode, street or certificate number.
- Data source: British Geological Survey GeoSure shrink-swellPrimary BGS dataset page for shrink-swell clay susceptibility, a key subsidence indicator.
- Data source: Police.uk crime dataOpen street-level crime data for England, Wales and Northern Ireland.
- Check this with: Ofcom broadband checkerOfficial checker for broadband availability and speeds.
- Check this with: Ofcom mobile coverage checkerOfficial predicted mobile coverage by network.
- Data source: Food Standards Agency food hygiene ratingsPublic register used to identify nearby food and drink venues.
- Official register: Ofsted inspection reportsSchool and provider inspection report lookup for England.
- Official register: Historic England National Heritage ListListed buildings, scheduled monuments and other protected heritage entries in England.