Auction Finance: How It Works, What It Costs, and the 28-Day Deadline
Win a property at auction, and the clock starts the moment the hammer falls. You pay a 10% deposit on the day, and you usually have just 28 days to pay the rest. A normal mortgage cannot be completed in that time, which is why auction buyers use auction finance. Arrange it before you bid, and you can buy with confidence. Leave it too late, and you risk losing both the property and your deposit.
This guide explains exactly how auction finance works, what it costs, and the one thing almost no other guide gives you: a simple way to work out your true maximum bid before auction day, so you never overpay. It also covers the legal pack trap and what actually happens if you cannot complete in time.
Auction finance is a form of bridging loan, arranged fast and secured against the property. If you are weighing it against a mortgage first, our guide on bridging loans vs mortgages explains the difference.
- Auction finance is a short-term bridging loan designed to complete within the 28-day auction deadline, often released in 5 to 14 days.
- You pay a 10% deposit on auction day, then auction finance covers the remaining balance before the deadline.
- Rates start from around 0.55% per month, with an arrangement fee of about 2%, plus valuation and legal costs.
- Your all-in cost is more than the hammer price, so work out your true maximum bid before you bid, not after.
- If you miss the 28-day deadline, you can lose your 10% deposit and be liable for the seller’s costs, so arrange finance before you bid.
What Is Auction Finance?
Auction finance is a short-term loan that lets you complete a property purchase within the tight deadline set by the auction house. It is a type of bridging loan, secured against the property you are buying, and it is built to be arranged in days rather than the weeks or months a mortgage takes.
It exists because the auction timetable does not fit normal lending. At a traditional, unconditional auction, the fall of the hammer is a legally binding exchange of contracts. You pay a 10% deposit on the day, and the balance is due within 28 days. A high street mortgage, which typically takes six to eight weeks, simply cannot meet that deadline, so auction finance fills the gap. You then repay it later by refinancing onto a mortgage or selling.
It is also more flexible on the property itself. Auction lots are often run-down, uninhabitable or unusual, exactly the properties a mainstream lender will not mortgage. Because auction finance is asset-based and short-term, it can lend against a property that could not be mortgaged in its current state, which is why investors and developers rely on it.
The 28-Day Countdown: Day by Day
Auction finance feels stressful because everything runs on a tight schedule. Here is the realistic timeline, and the single most important point: the work starts before auction day, not after.
| Stage | Timing | What happens |
| Before you bid | 1 to 2 weeks ahead | Get a decision in principle, review the legal pack, and set your maximum bid. |
| Auction day | Day 0 | You win, pay the 10% deposit, and exchange contracts. You are now legally committed. |
| Days 1 to 3 | First 72 hours | Your broker submits the full application, and the lender instructs the valuation. |
| Days 3 to 10 | Valuation and legals | A RICS valuation is completed, often in 48 to 72 hours, and solicitors act for both sides. |
| Days 10 to 20 | Funds released | The loan completes, and the balance is paid to the auction house. |
| Day 28 | Deadline | Completion must be done. A well-run case finishes with days to spare. |
The lesson is simple. Buyers who arrange finance before the auction complete comfortably. Buyers who wait until they have won are the ones who run out of time. A good broker will have a decision in principle ready before you bid, so day one is paperwork, not panic.
How to Work Out Your True Maximum Bid
This is where most auction buyers get caught out, and where no other guide gives you a clear method. Every guide tells you to factor your costs into your bid. Almost none shows you how. The number you can bid is not the loan the lender will give you. It is what is left after every other cost is covered. Work backwards from your cash, not forwards from the guide price.
Here is the calculation on a real example. You have £60,000 in cash and a lender offering a 70% loan-to-value on a refurbishment project you plan to sell.
| Line | Amount | Note |
| Your available cash | £60,000 | What you can put in |
| Less arrangement fee (2%) | -£3,500 | On the loan amount |
| Less legal and valuation fees | -£3,000 | Both sides, plus survey |
| Less Stamp Duty allowance | -£5,000 | Budget for it, due within 14 days |
| Less 4 months interest | -£4,900 | At around 0.7% per month |
| Less refurbishment budget | -£25,000 | Not usually covered by the loan |
| Cash left for the deposit | £18,600 | This funds your 30% deposit |
| Max bid | £62,000 | Deposit divided by 30% |
So although you have £60,000 in cash, your true maximum bid on this project is around £62,000, not the £85,000 or £90,000 a simple loan-to-value sum would suggest. Set that figure before the auction and do not exceed it, however tempting the room gets. This discipline separates profitable auction buyers from those who overpay and lose money.
What Auction Finance Costs
Auction finance is priced like bridging finance, because that is what it is. The rate looks small because it is charged monthly, but the real cost is the combination of interest over a short period plus the fees. Here is what to expect.
| Cost | Typical range | Notes |
| Monthly interest rate | 0.55% to 1.2% | Depends on loan-to-value and property |
| Arrangement fee | About 2% | Added to the loan or paid upfront |
| Valuation fee | £500 to £1,500+ | Payable early, often non-refundable |
| Legal fees, both sides | £1,500 to £3,000 | You pay the lender’s solicitor too |
| Auction buyer’s premium | Sometimes 1.5% to 4% | Charged by the auction house; check the pack |
| Exit or admin fee | Sometimes 1% | Check before you commit |
As a rough rule, budget total transaction costs of 3% to 6% of the purchase price, excluding Stamp Duty. Because the loan is short, the total interest is usually modest compared with the profit on a good auction deal. For a full breakdown of bridging costs, see our guide on how much bridging loans cost.
Review the Legal Pack Before You Bid
Every auction lot comes with a legal pack prepared by the seller’s solicitor. Reading it before you bid is essential, because once you win, you inherit whatever is in it. This is the step that catches out first-time auction buyers, and most finance guides ignore it.
Have your solicitor check the title register and plan, any restrictive covenants, tenancy agreements if the property is let, the searches, and especially the special conditions of sale. The special conditions can quietly shift costs onto you, such as paying the seller’s legal fees or a hidden buyer’s premium. A defect found after you have committed can delay the finance or sink the deal entirely.
Costs Hidden in the Legal Pack
- A buyer’s premium or administration charge payable on top of the hammer price, often £600 to £1,500 or more.
- An obligation to pay the seller’s legal costs, which can add £2,000 to £5,000.
- Ground rent or service charge arrears on leasehold lots that you inherit on completion.
- Restrictive covenants that limit what you can do with the property, which can affect your exit.
What Happens If You Cannot Complete in Time
This is the risk every auction buyer needs to understand before they bid, and the one most guides skip over. At an unconditional auction, winning the bid is a binding exchange of contracts. If you cannot complete within the deadline, the consequences are serious.
Under the RICS Common Auction Conditions, which most UK auctions use, the seller can charge you daily interest on the outstanding amount, often around 4% above the Bank of England base rate, for every day you are late. If you still cannot complete, the seller can keep your 10% deposit, re-sell the property, and pursue you for any shortfall between your price and the eventual sale price, plus their costs.
In short, failing to complete is expensive and legally serious. It is the single biggest reason to arrange your finance before you bid, not after you have won. With a decision in principle in place and the legal pack already reviewed, this risk is almost entirely removed.
An Expert View from Faisal Rashid
The buyers who get into trouble at auction are almost never the ones who could not afford the property. They are the ones who bid first and thought about the finance second. By the time they call me, the hammer has already fallen, and the clock is running.
My advice after twenty-five years is simple. Treat the finance as the first job, not the last. Get a decision in principle and have your solicitor read the legal pack before you ever raise your hand. Work out your true maximum bid and write it down. Do that, and auction finance stops being a gamble and becomes a tool.
Faisal Rashid, Founder of Westminster Finance. Former banker, MP and Mayor, with over 25 years in finance.
A Manchester Auction Example
The situation. A portfolio landlord spotted a run-down three-bedroom terrace in Oldham at auction, guided at £90,000. It needed a full refurbishment and could not be mortgaged in its current state. She came to us two weeks before the auction.
The preparation. We arranged a decision in principle for up to 70% loan-to-value, and her solicitor reviewed the legal pack and confirmed no hidden surprises. She set a firm maximum bid of £105,000 based on her cash, fees, interest and a £30,000 refurbishment budget.
The outcome. She won at £98,000. We submitted the application the next morning; the valuation was done within three days, and the £68,600 auction finance was completed on day twelve, comfortably inside the deadline. She refurbished over three months, then refinanced onto a buy-to-let mortgage that repaid the bridge and left the property cash-flow positive. The whole plan worked because the finance was arranged before she bid.
Get Ready Before the Hammer Falls
Successful auction buyers arrange their finance first. If you are eyeing a lot in Manchester or the North West, we can get you a decision in principle before auction day, so you bid with confidence and complete inside the deadline. Speak to our team early, ideally a week or two before the auction, and we will make sure the money is ready when you need it.
Frequently Asked Questions
How does auction finance work?
Auction finance is a short-term bridging loan arranged quickly, often before you bid, to fund an auction property purchase. You pay a 10% deposit on auction day, then the auction finance covers the remaining balance within the 28-day deadline. It is secured against the property and repaid later by refinancing onto a mortgage or selling.
How quickly can auction finance be arranged?
A straightforward case can be arranged in 5 to 14 working days, and some lenders can release funds even faster on qualifying deals. Most complete comfortably within the 28-day auction window, provided the application starts promptly and ideally has a decision in principle already in place before the auction.
How much deposit do I need for auction finance?
You pay a 10% deposit to the auction house on the day you win. For the auction finance itself, lenders typically want a deposit of 25% to 35% of the property value, so the loan covers 65% to 75%. The two work together: the 10% forms part of your overall deposit towards the purchase.
How much does auction finance cost?
Expect a monthly interest rate from around 0.55% to 1.2%, an arrangement fee of about 2%, valuation and legal fees, and sometimes an exit fee and a buyer’s premium. As a rough rule, budget total transaction costs of 3% to 6% of the purchase price, excluding Stamp Duty.
Can I get auction finance with bad credit?
Often yes. Auction finance is asset-based, so lenders focus on the property and your exit strategy rather than your credit score. Adverse credit is far less of an obstacle than it would be for a mortgage, though it may affect the rate. A strong deposit and a credible exit matter most.
What happens if I cannot complete within 28 days?
Under the RICS Common Auction Conditions, the seller can charge daily interest, often around 4% above the Bank of England base rate, for every day you are late. If you still cannot complete, you can lose your 10% deposit, and the seller can re-sell the property and pursue you for any shortfall. This is why finance should be arranged before you bid.
Should I review the legal pack before bidding?
Yes, always. The legal pack contains the title, searches, tenancy details and special conditions of sale, and once you win, you inherit whatever is in it. Hidden costs such as a buyer’s premium, an obligation to pay the seller’s legal fees, or restrictive covenants can all be buried there. Have your solicitor review it before you bid.
Can I use auction finance for commercial property?
Yes. Auction finance can be used for residential, commercial and mixed-use property, as well as land. It is particularly useful for commercial or mixed lots that need work before they can be let or refinanced onto a longer-term commercial mortgage.
What is the exit strategy for auction finance?
The exit is how you repay the loan at the end of the term. The two most common routes are refinancing onto a longer-term mortgage once the property is habitable, or selling the property. Lenders assess your exit closely before they lend, so it needs to be realistic and supported by evidence.
Do I need a survey as well as the lender’s valuation?
They are different things. The lender’s valuation confirms the property is adequate security and tells you little about its condition. On a run-down auction lot especially, a separate building survey is strongly advisable, because you are committed the moment the hammer falls and cannot renegotiate afterwards.
