Flood risk in the UK: who maps it and who insures it

Flooding is the natural hazard most British households are likely to meet. It rarely makes the national news the way a storm does, because most floods are local: a few streets under water after a cloudburst, a riverside terrace after a wet winter, a seafront when a surge coincides with a spring tide. The cost is still large, and the way the UK spreads it differs sharply from its neighbours across the Channel.

Three questions run through every flood decision a homeowner makes. Who decides how risky a place is? Who pays when the water comes in? And what can an owner find out before buying, insuring or rebuilding? The guides below answer each one in depth; this overview sets out how the pieces fit.

The scale of the risk in England

The most recent national picture comes from the Environment Agency’s National Assessment of Flood and Coastal Erosion Risk (NaFRA), published on 17 December 2024. It found 6.3 million properties in England in areas at risk of flooding from rivers, the sea or surface water. Of those, about 2.4 million are at risk from rivers and the sea and about 4.6 million from surface water; some properties face both.

Climate change pushes the number upwards. The assessment projects that, by the middle of the century, around 8 million properties could be in areas at risk, roughly one in four. Coastal erosion adds a separate and much smaller exposure: about 3,500 properties by 2055 and about 10,100 by the end of the century.

The surface water figure surprises people. It rose 43% compared with the previous assessment, which the Environment Agency attributes mainly to better modelling rather than worse weather. The practical lesson is that flood risk in England is not mainly about living next to a river. Many of the properties at risk sit on ordinary streets where rain cannot drain away fast enough.

Who maps flood risk in each nation

Flood mapping is devolved. Each nation has its own agency, its own maps and its own definitions of risk.

The differences go beyond branding. England rates long term risk as high, medium, low or very low, with “high” meaning a greater than 3.3% chance of flooding in any year. SEPA’s “high likelihood” means a flood expected on average once every ten years. Northern Ireland uses one set of probabilities for rivers and another for surface water. The same word can mean different things a few miles apart, which is why the maps guide listed below compares them side by side.

There is a second split within each nation, between maps made for planning and maps made for the public. Planning maps usually ignore flood defences at first, on the reasoning that a wall built today may not be maintained for the lifetime of a new house. Public risk maps usually include defences, because they describe the risk as things stand. Both are official, and both are correct for their purpose.

Local councils add a layer of their own. In England and Wales they lead on surface water and ordinary watercourses, and GOV.UK directs people with questions about surface water and flash flooding to their council.

What an owner can check before buying or insuring

England offers the most complete set of public tools. A buyer or owner can:

• look up the long term flood risk for the area around a postcode, with separate results for rivers and the sea, surface water, reservoirs and (where data exists) groundwater;
• see potential flood depths and how risk may change with climate change, added to the service on 28 January 2025;
• check the flood zone on the Flood Map for Planning, which matters for extensions and rebuilding;
• request the flooding history for an area;
• sign up for flood warnings through Check for flooding, or call Floodline on 0345 988 1188.

Every one of these tools describes areas, not individual buildings. The GOV.UK long term service says plainly that it “does not tell you how likely it is that an individual property will flood”. Floor levels, thresholds, air bricks and drainage decide what happens to a particular house, and only a survey or a look at the building itself can establish those.

The step-by-step method for reading a result, with the official band definitions and the NaFRA 2024 numbers, is in the long term flood risk guide.

Who pays when a home floods

The UK relies on private insurance for flood damage to homes. No law requires a household to buy flood cover, and none requires an insurer to offer it at any particular price.

That market worked reasonably well while insurers priced flood risk across a whole portfolio. As modelling improved and insurers began to price addresses individually, homes in high-risk areas faced steep premiums or refusals. The answer, set out in Part 4 of the Water Act 2014 according to the House of Commons Library, was Flood Re.

Flood Re launched on 4 April 2016. It is a reinsurer, not an insurer: households buy policies from ordinary insurers, and an insurer can pass the flood part of an eligible policy to Flood Re for a fixed premium set by Council Tax band. Every UK home insurer pays a levy towards the scheme, set at £160m a year from April 2025 according to Flood Re’s 2025-26 annual report. At 31 March 2026 the scheme held an estimated 353,000 policies.

Eligibility is narrow by design. Flood Re covers private residential homes built before 1 January 2009, in Council Tax bands A to H, with no more than three residential units in the building. Businesses, larger blocks of flats and housing association buildings are left out. The scheme is due to close in 2039, by which point flood cover is meant to be affordable without it.

The full rules, the premium table and the scheme’s finances are on the Flood Re scheme page. How cover works in practice for a household, including excesses and resilience measures, is in the home insurance guide.

How the UK model compares with the rest of Europe

Most of Europe takes one of three approaches to catastrophe cover, and the UK sits apart from all of them.

Compulsory attachment. France’s CatNat regime adds catastrophe cover by law to every property policy, funded by a flat surcharge, with a state-backed reinsurer behind it. Spain’s Consorcio de Compensación de Seguros does something similar through a surcharge on prescribed policies. Cover is close to universal because it comes with the ordinary policy.

Pools tied to fire insurance. Norway’s Natural Perils Pool and the Swiss system make natural-hazard cover automatic with fire or building insurance, at a uniform rate.

Voluntary cover with ad hoc state aid. In Germany, natural-hazard cover is an optional add-on, and after the July 2021 floods the federal government set up a reconstruction fund of up to EUR 30bn. Austria pays discretionary aid from a state fund.

The UK’s model is a fourth way: a voluntary private market, with a time-limited reinsurance pool funded mainly by insurers and aimed only at older homes. It keeps prices risk-based for most of the market, which preserves a signal about where not to build, and it avoids a taxpayer backstop. The cost of that design is the gaps it leaves: newer homes, businesses and anyone whose insurer declines to use the scheme. The schemes hub and the side-by-side comparison set out the European models in detail.

One more contrast matters for anyone reading European statistics. EIOPA’s dashboard on the insurance protection gap for natural catastrophes covers 30 EU and EEA countries and does not include the UK, so British figures have to come from national sources such as NaFRA and Flood Re’s own reports. The protection gap page explains what the dashboard measures.

A worked example: one street, three answers

Picture a street of 1950s semi-detached houses in a town in the English Midlands, running down to a brook that floods every few winters.

On the long term flood risk service, the houses at the bottom of the street show a medium risk from rivers and a high risk from surface water. The houses at the top show very low risk from both. On the Flood Map for Planning, the lower houses fall in Flood Zone 3, because the planning map sets aside the small embankment along the brook in its first step.

For the owner of a house at the bottom, each answer leads somewhere different. The planning zone matters if the owner wants to extend, because the local authority will apply the rules for high-probability areas. The long term rating matters for deciding whether to register for warnings and whether to fit flood doors or non-return valves. The insurance quote depends on the insurer’s own model, and because the house was built before 2009, is a private home and is in a low Council Tax band, the insurer can pass the flood element to Flood Re.

The owner at the top of the street needs none of this, apart perhaps from a glance at the surface water layer before buying. Two neighbours, a few hundred metres apart, live with entirely different flood questions.

The three UK flood guides

Each guide takes one of the questions above and goes into the detail:

• Long term flood risk in England: what the GOV.UK service shows, the four sources of flooding, the official meaning of each risk band, the NaFRA 2024 figures, and how to read a result before buying or insuring.
• Flood risk maps in the UK: planning flood zones, long term risk and surface water maps in England, Wales, Scotland and Northern Ireland, what each is for and the misreadings that come up most often.
• Home insurance for flood risk areas: how cover works, Flood Re eligibility and exclusions, what moves premiums and excesses, Build Back Better and the questions to put to an insurer.

What the numbers leave out

Official figures count properties in areas at risk. They do not count the people who live with the aftermath: weeks in temporary accommodation, damp walls that take months to dry, the anxiety of every heavy forecast. They also leave out much of the groundwater risk, which the 2024 assessment does not include because the evidence is insufficient; it cites earlier estimates of between 122,000 and 290,000 properties in areas at risk from groundwater.

Flood Re’s own board, in its 2025-26 annual report, describes the pressures on the scheme as “structural rather than cyclical”, pointing to the disproportionate share of exposure carried by higher-value homes and the limited reinsurance capacity available. That is a polite way of saying the arithmetic is getting harder. With 2039 thirteen years away from 2026 and the mid-century projection pointing to around 8 million properties at risk, the question of who pays for British floods after Flood Re closes has no settled answer yet.