Auction finance built around the 28-day clock.

The 28-day rule, and what you sign up to on the gavel

When the hammer falls at a traditional auction, you have exchanged contracts. There is no cooling-off period and no subject-to-finance clause. You pay the deposit, normally 10% of the hammer price plus the auctioneer’s buyer fees, on the day, and you are contractually bound to complete the remaining 90% within 28 days, sometimes 21, occasionally 14 on commercial lots. The conditions of sale fix the date; your financing problems are not the seller’s problem.

That timetable rules out a conventional buy-to-let mortgage, which averages eight to twelve weeks to offer and completion. Bridging is the standard funding route for auction stock because it is the only product class consistently capable of completing inside the window: 10 to 15 working days on a well-run case, as of June 2026 priced at 0.75% to 1.10% per month on residential first charges with an arrangement fee of typically 2%.

Get credit-backed terms before you bid, not after

The single biggest determinant of whether an auction purchase completes calmly or chaotically is what happened before auction day. Done properly, the sequence runs: legal pack reviewed, lender terms credit-backed against the specific lot, valuation type agreed, maximum bid set by the funding maths rather than by enthusiasm. Then you bid knowing that day one of the 28 starts with a lender already committed in principle, not with a search for one.

An online "decision in principle" generated in 60 seconds is not that. Credit-backed terms mean an underwriter has seen the lot, the legal pack headlines, your experience and your exit, and has priced the actual risk. We turn these around in 24 to 48 hours from receiving the catalogue details, and where you are bidding on several lots we agree a framework with the lender covering your criteria, so any lot you win drops straight into an open file.

The legal pack, and why your solicitor matters more than your lender

Auction lots are sold with the defects priced in, and the defects live in the legal pack: special conditions that load the seller’s costs onto you, unadopted roads, missing building regulations sign-off, restrictive covenants, short leases, tenancies that do not match the catalogue description. The lender’s lawyers will find these in week three. You need to find them in week zero, because after the gavel they are your problems at your cost.

This is why we say the solicitor is the critical appointment. A bridging lender can move in days; a solicitor who has never run an auction completion cannot. Use one who reviews legal packs pre-bid as a fixed-fee service, accepts undertakings, and is comfortable with title insurance where searches will not come back in time. We will tell you candidly if your chosen firm is going to cost you the deadline, and we work alongside auction-fluent firms every week.

Valuation options and timing

The valuation route is a lever we pull deliberately. A desktop saves a week and several hundred pounds but caps LTV with some lenders; a full inspection unlocks the top of the LTV range but eats the schedule. On a 28-day clock we usually instruct the valuation the day terms are signed, before the legal pack review is even finished, because the valuer’s diary is the least controllable item on the critical path.

Unmortgageable stock: where auction bridging is the only route

A large share of auction inventory is there because it cannot take a mortgage in its current state: no working kitchen or bathroom, leases under 70 years, structural movement, Japanese knotweed, non-standard construction, fire-damaged or part-stripped interiors. Term lenders decline these on habitability and security grounds, which suppresses the buyer pool and the price. Bridging lenders underwrite the end state instead of the current one, so the investor who can fund the purchase and the cure buys at a discount that mortgage-dependent buyers cannot reach. Where works are needed, the bridge and the works funding combine into refurbishment finance.

The exit: term buy-to-let or sale

The exit is agreed before the bridge is written. For hold strategies, the cleanest structure is bridge-to-let, where the bridge and the buy-to-let exit are underwritten together, often by one lender on one valuation, so the refinance is pre-agreed rather than hoped for. For trade strategies, the sale exit is tested against realistic local marketing periods, not optimism. Either way the exit must survive scrutiny at today’s rates, because the bridge is only ever a countdown to it.

Worked example: £210,000 hammer price on a 28-day contract

A three-bed terrace, guide £180,000, knocked down at £210,000. Habitable but dated; the plan is a light refresh and a hold. The buyer pays £21,000 deposit plus £1,600 auctioneer fees on the day, leaving £189,000 due by day 28.

Timeline: terms credit-backed two days before the auction, desktop valuation back day 3, legal pack already reviewed so enquiries were minimal, completion day 16 of 28. The exit, a five-year buy-to-let fix at the post-refresh value, was evidenced to the bridging underwriter at application. Run your own lot through the bridging loan calculator to see the gross-to-net and total-cost maths before you set a maximum bid.