Auction Property Insurance: Cover From Exchange, Not Completion

Why the auction timeline breaks the normal insurance rule

In a standard residential purchase, you arrange buildings insurance to start on the day you complete — because that's the day risk passes to you. Auction doesn't work like that. Under the standard conditions used by most UK auction houses, risk in the property (and the buyer's obligation to insure it) passes at exchange of contracts, which happens the moment the gavel falls or the online bid is accepted. Completion is typically 20 working days later.

That means for the entire completion window, you are financially exposed to fire, flood, storm damage, subsidence and vandalism on a building you don't yet legally own outright but are contractually bound to buy. If it burns down on day 12, you still have to complete and pay the full price — the seller's insurance, if it even still exists, is not your safety net.

Most first-time auction buyers don't find this out until they read the special conditions in the legal pack, by which point they've already bid. Check for it before auction day using our legal pack guide.

What the legal pack tells you

The special conditions of sale will usually state one of three things:

• "The buyer insures from exchange" — the most common wording, and the one that catches people out.
• "The seller will maintain existing insurance until completion" — rarer, but check the sum insured is adequate and that the policy doesn't lapse for vacant possession reasons (see below).
• Silence — if the pack doesn't address insurance at all, the Common Auction Conditions (used by most auction houses, including the RICS/NAEA-endorsed sets) default to buyer-insures-from-exchange. Assume the worst case and insure anyway.

Read this clause before bidding, not after. If a lot is a burnt-out shell or derelict with no roof, some insurers won't touch it at any price, and that changes your risk calculation on the guide price itself.

Vacant property insurance is not the same as normal buildings cover

Most auction lots are unoccupied at the point of sale — that's often exactly why they're in auction. Standard buildings insurance policies usually contain an unoccupancy clause that suspends or voids cover after 30 or 60 days empty, sometimes with automatic exclusions for escape of water or malicious damage. If you try to insure an auction purchase on a normal homeowner policy, don't be surprised if a claim is rejected because the property has been vacant for three months already.

What you actually need for most auction purchases is a specialist unoccupied/vacant property policy:

• Covers empty properties (some insurers require monthly visits and proof of them — check logs, not just intention)
• No 30/60-day unoccupancy exclusion
• Priced on vacancy, condition, and whether the property has services connected
• Typically £15–£40/month for a straightforward vacant terrace, rising sharply for properties with roof damage, no working services, or known subsidence history

A handful of specialist insurers (Home Protect, Adrian Flux, Trinity Lane, and auction-specific brokers) will quote same-day, which matters because you need this live from the moment you win the lot — not next week.

Worked example

Say you win a two-bed mid-terrace in the Sheffield (S) postcode area — one of our busiest areas for auction listings — at a guide price of £68,000, against a modelled value of £150,000+ once refurbished (roughly in line with the 134% median modelled upside our data shows across current Best Buy lots). The property has been empty eight months, no gas connected, minor roof slip.

• Exchange happens at the fall of the hammer. From that second, you're liable.
• A standard homeowner policy would likely decline the property outright due to vacancy + roof condition.
• A specialist vacant property policy quotes £58/month (£1.5m rebuild sum insured, minimal contents), payable immediately by card, cover starting that day.
• Completion is set for 20 working days out — so you're carrying roughly one month's premium, around £58, against a £68,000 asset, until you own it outright.
• If a storm strips more of the roof in week two, the specialist policy pays out for the repair; without it, you'd be funding that repair yourself on a property you don't yet legally own and can't yet remortgage.

That £58 is trivial next to the exposure it removes. Compare it to your total costs on the deal — see our auction fees breakdown for how insurance sits alongside buyer's premium, legal fees and bridging costs.

Getting it right before you bid

1. Check the legal pack's insurance clause before the auction, not after — it tells you whether you're insuring from exchange.
2. Get an indicative vacant-property quote in advance for any lot you're seriously bidding on, especially ones with visible damage or long-term vacancy — a rejected application post-auction leaves you exposed with no cover and no time.
3. Have the insurer's details and payment method ready so cover can bind within minutes of winning the lot, not the next working day.
4. Re-check the sum insured against rebuild cost, not market value — rebuild costs for older or non-standard construction can exceed the purchase price.
5. Keep proof of vacant-property visits if your policy requires them; a lapsed inspection schedule is one of the most common reasons insurers decline claims on empty properties.

Browse live lots with legal packs already flagged on Below Hammer's deals page and check the insurance clause before you register to bid.