Your Score Is Not What the Lender Sees
Quick confession from the broker side of the desk. The number you check in a banking app means very little to the underwriter deciding your mortgage. Lenders do not buy that number. They buy your credit file, the raw record of every account, every payment and every search, and they feed it into a scorecard they built themselves and will never show you. Which is why two lenders can look at one file and disagree. Honestly, it happens every week.
That does not make the app number useless. It tells you roughly how you are doing and which way you are heading. Just do not treat 780, or 540, or whatever it says, as a verdict.
So what does move the decision? The history. Did you pay on time, how much of your limit do you live on, and is there a judgment or a default lurking in there somewhere? Clean file, plenty of lenders, decent rates. Messy file, fewer lenders and a pricier deal, though rarely a flat no.
And credit is only one voice in the room. Income, how long you have been in the job, the size of the deposit, the monthly commitments already leaving your account: they all get a vote. Strong credit with stretched affordability gets turned down. A bruised file with a big deposit and a steady salary often sails through.
Three Agencies, Three Different Numbers
Experian, Equifax, TransUnion. Those are the three agencies holding your file in this country, and no, they do not all hold the same thing, because lenders choose which of them to report to. Each has its own scale as well. Experian recently lifted the ceiling on its own. TransUnion is part-way through changing from a 0 to 710 range to 0 to 999, with the rollout running from late September 2026 to June 2027, so you may even see two different TransUnion scores side by side for a few months. Confusing? Yes. A 600 at one agency is not a 600 at another.
So stop chasing a magic figure. Find the band you are in (poor, fair, good, excellent) and ask what is holding you back.
What Actually Shifts Your Score
None of the agencies publish the recipe, but the ingredients are no secret. Missed payments are the big one, and it does not matter whether it was a credit card, a phone contract or the gas bill. Next comes how much of your credit you use, because a card sitting near its limit looks like somebody struggling. Age matters, since older accounts help. A burst of new applications hurts. Judgments, defaults and insolvencies hurt a great deal. And, dull but true, being on the electoral roll at your current address helps the agencies confirm you are who you say you are.
How Lenders Weigh the Past
Recent counts for more than old. Miss a payment last month and it stings. Miss one five years ago and it barely registers.
A county court judgment (CCJ) stays on your file for six years from the date it was issued, although if you pay it in full within a month it can be wiped from the record entirely. Defaults also run to six years. A settled one looks better than an unsettled one, but it is still visible to anyone who looks.
Before any application, get a report from all three agencies and lay them next to each other. The details do not always line up. Find the mistake now, not after a lender has already searched your file.
Searches: the Bit People Get Wrong
Looking at your own file is a soft search. Nobody else can see it, it does not touch your score, and you can do it as often as you like. Plenty of lenders will give you an agreement in principle off a soft search, though a few insist on a hard one, so ask before you hand over your details.
A hard search is the real thing. It goes on your file when you make a formal application, other lenders can see it, and it can stay there for up to two years (most of them look hardest at the last twelve months). One is nothing. Five in a month reads like panic.
This is a big part of why I like a broker doing the groundwork first. A decent one usually knows which lenders will take your file before anything formal gets submitted.
What the Underwriter Is Checking
Credit history, obviously. Then income and employment: payslips if you are employed, accounts if you work for yourself. Then outgoings, meaning the debts that leave your account every month before the mortgage does. Then your deposit, and the loan-to-value that falls out of it. Finally the property itself: value, condition, construction, all picked over by the valuer.
All of that feeds the affordability test, which boils down to one question. Could you still manage if rates went up? A clean file can speed things along. Missing documents and a slow valuer will undo that gain inside a week. Once it is all through, the formal offer lands with its terms attached.
What Decides Your Rate
Think in tiers. Clean file and a reasonable deposit get you the cheapest tier. Adverse marks put you in a dearer one, or sometimes with a specialist lender altogether. Exactly how much dearer depends on how bad the problem was and how recent. I am deliberately not quoting a figure, since rates move week to week. The current spread is on our mortgage rates page.
Credit is only part of it. The deposit counts for a lot. The product counts too: a fixed rate gives you certainty, a tracker follows the Bank of England base rate, and neither wins by default. Then each lender layers on its own cost of borrowing, which swings with the wider economy. Hence two quotes on the same morning can look nothing alike.
Loan-to-Value in Plain English
Loan-to-value (LTV) is the loan expressed as a percentage of what the property is worth. Here is a made-up example to show the sums. Say the house is £200,000 and you put down £40,000, which is 20%. You borrow the other £160,000, so your LTV is 80%.
Lower LTV generally means cheaper deals, with the price steps landing near the 60, 75 and 90 per cent marks. Push the LTV higher and approval gets harder while the rate climbs. And yes, lenders also look at what else you owe, because less debt helps.
Tidying Your File Before You Apply
Boring advice, but it works. Pay everything on time. Set up direct debits for at least the minimum and you remove the risk of forgetting. Get card balances down, with under roughly 30% of each limit the usual target. If you are not on the electoral roll, fix that this week.
Then, and I know this is the hard part, stop applying for credit. Store cards, buy now pay later (where it gets reported), a new phone on finance: every one of them counts. Leave it alone for a few months before applying, and if you really do need something, space it out.
When the File Is Wrong
Mistakes on credit files are more common than you would think. Read each report slowly. You are hunting for accounts you do not recognise, wrong balances, an old address, or a link to someone you no longer share finances with, like an ex-partner. Spot something? Dispute it with the agency and it will ask the lender to confirm. You can also go straight to the lender, because they hold the original record.
If you suspect fraud, tell the agencies and your bank today. Identity fraud trashes a score quickly.
Corrections take a few weeks. Do not put an application in the day after you raise a dispute.
When the Answer Is No
Nobody enjoys a decline. It does at least tell you something.
The usual reasons are a low score or adverse items, a thin file (very common with first-time buyers, who simply have not borrowed before), a deposit smaller than the lender wants (plenty ask for at least 5%), or affordability that falls short because the income does not support the loan. Recent CCJs, defaults and missed payments get treated as red flags too.
So what now? Ask the lender why. If they used a credit file, ask which agency supplied it, so you check the right one. Go through all three reports. Pay down what you can and give the lower balances time to show. Save a bigger deposit if that was the problem. And hold off reapplying, because every formal application can leave a hard search, so sort the cause first. Soft searches are fine while you think it over.
Then talk to a broker, who will know which lenders are stricter about your circumstances and which are kinder.
Where a Broker Comes In
Every lender handles missed payments, CCJs and defaults differently, and none of them publish the rules. Brokers know them. We place applications where they have a chance and steer clear of lenders that would say no, which saves you hard searches you did not need. Whole of market, and the first conversation costs nothing.
Frequently Asked Questions
What credit score do I need to get a mortgage in the UK?
There is no magic number.
Each lender builds its own scorecard and keeps the cut-off private. A clean, recent record gives you the widest choice, while recent arrears, a default or a CCJ will steer you towards specialist lenders. Ask a broker where you are likely to land before you apply, not after.
Does checking my credit score hurt my mortgage application?
No.
Looking at your own score or report is a soft search, which lenders cannot see and which leaves your score alone. The hard search is the one to watch. It is logged when you apply formally, and a handful of them close together will count against you.
Can I get a mortgage with a CCJ or a default?
Often, yes.
The lender will want the date, the amount and whether you have settled it. Old, small and paid off is much easier than recent and unpaid. Plan on a larger deposit, a higher rate and a specialist lender.
How long do missed payments, CCJs and defaults stay on my credit file?
Six years for each, counted from the date recorded.
The one exception is a CCJ paid in full within a month of being issued, which can be removed. Hard searches can linger for up to two years, but most lenders only weigh the last twelve months.
Which credit reference agency do mortgage lenders use?
It depends on the lender.
Some check one, some two, some all three, and they will not tell you which beforehand. So look at all three reports. A tidy file at one agency can hide a mess at another.
How long before I apply should I start improving my credit score?
Three to six months if you can manage it.
Paying down cards and joining the electoral roll can show quickly. Last year’s missed payment will not disappear, though it counts for less with every clean month behind it.
Speak to a mortgage specialist
Not sure how a lender will read your file? Ask us before you apply.
UK Mortgage Broker is a whole-of-market broker helping clients throughout the UK and globally to secure funding on UK property. We are directly authorised and regulated by the Financial Conduct Authority.
Your home may be repossessed if you do not keep up repayments on your mortgage.
Call: +44 1628 969 500 Email: info@uk-mortgagebroker.co.uk
Related Pages
- How a Mortgage Application Impacts Your Credit Report – What a formal application leaves on your file, and how long lenders can see it.
- Mortgage Declined After Agreement in Principle – Why a lender can say no after an early yes, and what to do next.
- Documents You Need for a Mortgage Application – The paperwork lenders ask for, so nothing holds up your case.
- How Much Can I Borrow? – How lenders turn your income and commitments into a maximum loan.
- Residential Mortgages – Home-mover and purchase mortgages from a whole-of-market broker.