When should you start saving for a mortgage deposit?

Start saving for a home when there is room in your budget to do it consistently, even if your moving date is uncertain. There is no ideal birthday or salary at which everyone should begin. The useful question is how much you can put aside without leaving ordinary bills, essential spending or unexpected costs uncovered.

You are usually saving towards a deposit and the other costs of buying. The mortgage is the borrowing that may fund the remainder. Having a deposit does not, by itself, mean a lender will approve the loan.

Give the target a postcode and a price range

Choose a type of home and an area you could realistically consider. A one-bedroom flat and a three-bedroom house need different budgets, even on the same street. Start with a price range rather than one dream property.

MoneyHelper's deposit guide says buyers usually need at least 5% to 10% of the purchase price. Mortgage eligibility and the deposit required depend on the lender and your circumstances. A larger deposit may give you access to different deals, but it is not sensible to empty every emergency pot just to reach a percentage.

For illustration, a £240,000 purchase would need £12,000 for a 5% deposit or £24,000 for 10%. Those figures describe the arithmetic, not an estimate of what you could borrow.

Work backwards from the amount still missing

Subtract savings you can genuinely use from the deposit target. Divide the gap by a monthly amount you could sustain. The table uses an illustrative £12,000 target and £3,000 already saved, leaving £9,000 to find.

Monthly saving	Time to add £9,000
£250	36 months
£375	24 months
£500	18 months

These examples ignore interest, bonuses, fees and changing house prices. They also exclude purchase costs. Use them to test a plan, then revisit the target as prices and your circumstances change.

If the result feels too long, change one assumption at a time: the property budget, area, moving date or sustainable saving amount. A target that depends on never replacing a broken appliance is too fragile.

Keep buying costs separate

Budget beyond the deposit for legal work, a suitable survey, any mortgage fees, removals and initial essentials. Property transaction taxes depend on where you buy and your circumstances. Use MoneyHelper's buying and moving cost guide to build a separate checklist and obtain actual quotations where possible.

Keep the emergency money distinguishable from the house fund. If an annual bill comes out of “the deposit”, the number on the savings screen is overstating your progress. A separate pot for known annual expenses can make your monthly saving figure more honest.

Check the Lifetime ISA rules before choosing one

A Lifetime ISA can help eligible first-time buyers, but the conditions matter. Under the current government rules, you normally open one from age 18 and before 40, can contribute up to £4,000 a year until 50, and receive a 25% government bonus. Eligibility and residency rules apply.

For a qualifying first-home purchase, the price must be £450,000 or less, at least 12 months must have passed since the first payment, and a solicitor or conveyancer handles the withdrawal. A mortgage is required and further conditions apply. Other withdrawals usually face a 25% charge unless an exemption applies. That charge can remove some of your original savings as well as the bonus.

Do not choose an account on its headline bonus alone. Consider access, eligibility, the likely property price and when you expect to buy. Check the provider's terms and get regulated advice if you need a recommendation for your circumstances.

Make the first month easy to repeat

Review recent spending, choose an affordable amount and arrange a transfer after payday. After three months, check whether the plan survived real life. Increase it only if the budget supports the change.

As buying becomes a realistic next step, ask a lender or regulated mortgage adviser about affordability and the documents they need. A deposit timetable helps you prepare; an affordability assessment establishes what borrowing might actually be available.