Commercial Flood Insurance in 2026: Rising Excesses, Exclusions, and How Monitoring Data Strengthens Your Renewal

UK insurers paid out a record £6.1 billion in property claims in 2025 — the highest annual total since the Association of British Insurers (ABI) began collecting the data in 2017. Within that, weather-related property claims reached £1.2 billion, a 14% increase on 2024, spread across domestic, commercial and business interruption lines. For anyone responsible for a portfolio of commercial properties, those numbers explain what you are probably already seeing at renewal: commercial flood insurance is getting harder to buy, more expensive to hold, and more conditional on evidence that you actually manage the risk.

This post looks at what is driving the hardening market, where the coverage gaps sit for businesses, and — most practically — what underwriters want to see at renewal and how flood monitoring data, response plans and incident logs can strengthen your negotiating position.

Two record years in a row

The 2025 figures did not come out of nowhere. In February 2025, the ABI reported that 2024 had already set a record: £585 million paid out for weather-related damage to homes and possessions — £127 million more than the previous year — during a storm season that produced twelve named storms, the most since 2015/16. Total property claims for 2024 reached £5.7 billion, itself a record at the time.

Then 2025 topped it. Alongside the £6.1 billion headline, the ABI's full-year data shows domestic flood claims rose 38% to £312 million, and the average flood payout to a homeowner jumped 60% to around £30,000. Those are household figures, but the commercial lines followed the same trajectory: the ABI's quarterly data recorded £109 million paid to businesses for weather-related damage and business interruption in Q1 2025 alone, and a further £124 million in Q2.

Behind every one of those claims is a disrupted household or business — premises out of action, stock written off, staff displaced, trading interrupted for months. The insurance market's response to two consecutive record years is rational, but it lands hardest on the organisations least able to absorb it: multi-site operators with even a handful of properties in higher-risk locations.

Why commercial flood insurance is hardening

Three forces are converging on commercial property owners and their advisers.

More properties are classified as at risk

The Environment Agency's updated National Assessment of Flood Risk (NaFRA), published in December 2024, found that 6.3 million properties in England are in areas at risk of flooding from rivers, the sea or surface water — and projects that figure to reach around 8 million, roughly one in four properties, by mid-century under central climate projections. The new assessment integrates detailed local models and current Met Office climate projections, which means underwriters now have far more granular data about individual sites than they did even five years ago. A postcode that was acceptable at your last renewal may sit in a different risk band today, not because anything changed on the ground, but because the mapping got better.

Flood Re does not cover businesses

Flood Re, the joint government-industry reinsurance scheme that keeps household flood cover affordable, explicitly excludes commercial property. The scheme's own guidance confirms that businesses are ineligible, alongside most leasehold blocks and homes built after 2009. When Parliament debated the reform of Flood Re on 1 July 2026, the exclusions were acknowledged, but the announced reforms focus on the household market and the transition to risk-reflective pricing by 2039 — including a pilot of "flood performance certificates" that would let householders' resilience measures be reflected in premiums. There is no equivalent safety net for commercial premises. The British Insurance Brokers' Association (BIBA) operates a commercial flood scheme, launched in December 2016 and underwritten through Lloyd's, for businesses that struggle to find cover — but it is a broker-arranged solution, not a subsidised backstop.

The practical consequence: a commercial property in a high-risk location faces the full, unsubsidised market price of its risk. And that price is increasingly expressed not just in premium, but in policy structure.

Excesses and exclusions are doing the rationing

Specialist flood brokers report that most mainstream commercial insurers now apply one of three responses to a property in Environment Agency flood zones 2 or 3, or with a recorded flood claim: a flood exclusion, a substantially increased flood excess, or a declined quote. Where cover is offered on the standard market, brokers report five-figure flood excesses in higher-risk cases — which can render the policy of limited use for the most likely loss scenario at that site. For portfolio operators, this shows up as a patchwork: 180 sites renew cleanly, while a dozen in river valleys or coastal towns attract special terms, separate excesses, or exclusions that quietly shift the risk back onto your balance sheet.

If any of this is on your renewal schedule now, the question is no longer "how do we get a cheaper premium?" It is "how do we demonstrate that these sites are better risks than the postcode data suggests?"

What underwriters actually want to see at renewal

An underwriter pricing flood risk on a commercial portfolio is working from models and mapping. Anything you can present that demonstrates the model overstates your exposure — or that your organisation would materially reduce the loss if water did arrive — is negotiating capital. In practice, that evidence falls into four categories.

1. Site-level risk knowledge

A schedule that lists each property with its flood source (river, surface water, tidal), its proximity to watercourses and its risk band shows the underwriter you understand your own exposure. It also lets your broker argue individual sites down: national mapping works at area level, and a site that sits on locally raised ground, behind a defence, or above the storey at risk may deserve better terms than its postcode. If you have not looked at your portfolio's exposure recently, start there — the pattern of wetter winters and more intense storm rainfall is precisely what the NaFRA update and insurer models are pricing in.

2. A documented flood response plan

Underwriters distinguish between a business that would watch the water come in and one that would act. A written flood plan — who is alerted, at what trigger level, who moves stock and isolates services, how the site communicates with tenants or staff — is direct evidence of the second kind. It matters because so much of a commercial flood loss is avoidable in the final hours before inundation: stock lifted off ground level, vehicles moved, electrical systems isolated, flood barriers deployed. If you do not yet have one, our business flood plan checklist and runbook sets out a structure you can adapt per site. A plan that names real people and real trigger thresholds reads very differently from a generic template.

3. Evidence of live monitoring

A response plan is only credible if the business would actually know a flood was coming. This is where monitoring data earns its keep at renewal. Being able to state — and evidence — that every site in the portfolio is monitored against official Environment Agency, Natural Resources Wales and SEPA flood warnings, with river level, rainfall and tidal data refreshed every five minutes and named responders reviewing the dashboard, converts your flood plan from a document into an operational capability. It answers the underwriter's unspoken question: would anyone actually be watching? For multi-site operators, doing this manually — checking three government websites separately, per site, per day — does not scale and does not produce an audit trail. A portfolio dashboard that monitors flood alerts across every site does both.

4. An incident and near-miss log

Perhaps the most underused asset at renewal: a dated log of every flood warning that affected a site, what the team did in response, and what the outcome was. A record showing that a site received three flood alerts in the last two years, that the response plan was activated each time, and that no loss followed, is compelling evidence that the site's managed risk is lower than its modelled risk. It is exactly the logic behind the flood performance certificates now being piloted in the household market — resilience action, evidenced, reflected in terms. Commercial operators do not need to wait for a certificate scheme to make that argument; they need the records.

Presenting this well matters as much as having it. Ask your broker what format the underwriter prefers, and aim for a short risk-management pack per higher-risk site: risk summary, plan, monitoring arrangement, incident log, plus photographs of any physical resilience measures (barriers, raised electrics, non-return valves). Brokers consistently report that a well-evidenced submission gets access to markets and terms that a bare schedule of values does not.

Where FloodWatch fits

FloodWatch was built for exactly this operational layer. It aggregates official flood warnings from the EA, NRW and SEPA into one portfolio dashboard, refreshes river level, rainfall and tidal data every five minutes, and shows what has changed since your team last checked. Sites are onboarded in bulk by CSV and mapped with Ordnance Survey geocoding, so a 50- or 200-site portfolio is monitored on one screen rather than across three national websites. When an event does occur, AI-generated incident briefs and PDF exports give you the dated, site-specific record that a renewal submission — or a claim — needs. Our ongoing research programme into per-site risk scoring and historical trend analysis is aimed at deepening exactly this evidence base over time.

None of this replaces a broker, and none of it changes the weather. What it changes is the story you can tell an underwriter: not "we hope it doesn't flood", but "we know our exposure, we watch it in real time, and here is the log that proves it".

The renewal conversation is winnable

Commercial flood insurance in 2026 reflects two record claims years, sharper risk mapping, and a market with no Flood Re safety net for businesses. Higher excesses and exclusions are how insurers are managing that reality — but terms are not fixed. Underwriters price uncertainty, and evidence removes uncertainty. A portfolio that arrives at renewal with site-level risk knowledge, live monitoring across all three national agencies, a rehearsed response plan and a clean incident log is a demonstrably different risk from the postcode average — and can be priced as one.

Explore how FloodWatch helps property portfolios build that evidence base on our features page — or see how it works for your own sites before your next renewal cycle begins.