Mortgage Calculators
Mortgage Deposit Calculator
Work out what deposit you need, how long it will take to get there, and what that deposit is actually worth in lending terms.
- Deposit needed for your target price
- How long to save it at your current rate
- The LTV band it puts you in
- What each extra percent unlocks
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rates, fees & total borrowing
Assumes a flat monthly amount, no interest on savings and a fixed purchase price. Stamp duty, legal fees and a survey sit outside the deposit. This is an estimate based on typical lender criteria and current rates. It is not advice, a recommendation, or an offer of credit. What you can actually borrow depends on your circumstances and the lender's own assessment.
Deposit and loan to value thresholds reflect common lender practice rather than any single lender. Correct as at 15 August 2026; criteria change without notice.
How much deposit do you actually need?
Five per cent is the usual minimum on a residential purchase, and it is genuinely available, but it is the tightest part of the market. Ten per cent widens your options considerably, and fifteen per cent moves you into territory where most lenders will look at the case on its own merits.
The deposit is not the only cash you need. Stamp duty, legal fees, a valuation, searches and moving costs all come out of the same pot, and a deposit that leaves nothing behind it is a fragile position. Lenders also look more favourably on applicants who are not stripped bare by completion.
If your credit file has any adverse on it, the arithmetic changes. The lenders most willing to accept adverse credit are generally the least willing to lend at high LTV, so the deposit is doing double work: it buys a better rate, and it buys access to lenders who would otherwise decline you outright.
What the timeline actually looks like
Saving £500 a month towards a 10% deposit on a £250,000 property means £25,000, which takes 50 months, or a little over four years. Push to £750 a month and it is 34 months. Drop the target to 5% and £500 a month gets you there in 25 months. Seeing those three numbers side by side usually changes the plan.
A Lifetime ISA is worth understanding before you start. The government adds 25% to what you pay in, up to £4,000 a year, so £4,000 saved becomes £5,000. There are conditions, including a penalty for withdrawing for anything other than a first home or retirement, and a property price cap. For a first-time buyer saving over several years it is often the single biggest lever available.
The calculator assumes a flat monthly amount and a fixed purchase price. In practice house prices move, and if prices rise faster than you save, the deposit target moves away from you. That is an argument for reviewing the plan annually rather than setting it once and forgetting it.
The money you need that is not the deposit
Stamp duty is the big one, and for anyone who is not a first-time buyer it starts at £125,000. On a £300,000 purchase a home mover pays £5,000. Legal fees and searches typically run to £1,500 to £2,500. A survey is anywhere from a basic valuation to £1,000 or more for a full building survey. Removals, and the first month of living somewhere with no furniture, add more.
Lenders also look at what is left. Completing with nothing behind you is not a criteria failure in itself, but affordability assessments include a stress test, and an applicant with no reserves is more exposed to the exact scenario that stress test is modelling.
A sensible rule is to treat the deposit and the costs as two separate savings targets and reach both before you start viewing. It is far less painful than discovering the gap two weeks before exchange.
Where to go next
Independent sources
- MoneyHelper: what can I afford? — Free and impartial guidance on setting a realistic budget
- GOV.UK: Lifetime ISA — The 25% government bonus on first-home deposit savings
Tell Us What You Are Saving Towards
Tell us your target and what you have so far. We will tell you what deposit the lenders you are aiming at will actually want.
Enquiry Form
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Read More About Deposits
Knowing the number is one thing. Where it comes from is what the lender asks about.
How Much Deposit Do You Need?
What each deposit size actually reaches, and what staying small costs you.
Gifted Deposits
How a family gift is evidenced, and what the person giving it has to sign.
Where a Deposit Can Come From
Savings, gifts, equity and the sources lenders will not accept.
First-Time Buyer Advice
Putting the deposit, the borrowing and the timing together for a first home.
Work out the deposit you actually need
The deposit is only part of the money you need up front. Tell us what you are saving towards and we will map the full picture.
Frequently Asked Questions – Mortgage Deposit Calculator
How much deposit do I need for a mortgage?
Five per cent of the purchase price is the usual minimum on a residential mortgage. Ten per cent gives you access to considerably more lenders and better rates, and at fifteen to twenty per cent you are into the mainstream of the market.
Can I get a mortgage with a 5% deposit?
Yes, on a clean credit file and subject to affordability. It is the most restricted end of the market though, with fewer lenders and higher rates. With adverse credit on your file, 95% lending becomes very difficult and most specialist lenders will not go there at all.
Does a bigger deposit help if I have bad credit?
It helps a great deal. A larger deposit reduces the lender’s risk, which is exactly what an adverse credit case needs. It can be the difference between a decline and an offer, and it usually moves you into a cheaper tier as well.
Can my deposit be gifted?
Usually yes, most commonly from a parent or close family member. The lender will want written confirmation that it is a gift rather than a loan, that the giver has no interest in the property, and evidence of where the money came from.
Do I need extra money on top of the deposit?
Yes. Stamp duty where it applies, legal fees, searches, a valuation or survey, and moving costs all sit outside the deposit. It is sensible to budget for these separately rather than eating into the deposit itself.
Does this calculator account for interest on my savings?
No, it assumes a flat monthly amount with no growth, and a fixed property price. Both of those will move in practice, so treat the timescale as a planning guide rather than a precise date.