Mortgage Deposits: How Much You Need

The deposit is the single biggest hurdle between most people and a first home, and the single biggest lever over what a mortgage costs once they get there. Save more, and you unlock better rates and a wider choice of lenders. Save less, and you can still buy, but you pay for it in the interest rate for years.

This guide explains how much deposit you really need in 2026, how the size of your deposit shapes your interest rate through loan-to-value, and the practical routes to building one faster. Vetted Wealth matches you with independently vetted, FCA-regulated mortgage advisers, what follows is information to help you plan, not personal advice.

How much deposit you need

The absolute minimum for most buyers is 5% of the purchase price, and 95% mortgages are once again widely available in 2026. On a £250,000 home, that 5% is £12,500. A small number of lenders go further with 100% or family-backed deals, but for the mainstream market 5% is the floor and a deposit of 10% or more is where the choice really opens up.

It helps to separate two questions that often get muddled. The first is how much deposit a lender will accept, often just 5%. The second is how much you should aim for to get a good deal, usually more. The two are rarely the same number, and the gap between them is where a lot of money is quietly won or lost over the life of a mortgage.

How much a lender will then advance on top of your deposit is a separate calculation based on income and affordability. Our guide on how to get a mortgage in the UK walks through that side; here we focus on the deposit itself and the outsized effect it has on your rate.

Loan-to-value and your rate

Lenders express your mortgage as a loan-to-value (LTV), the percentage of the property’s value that the loan covers. Put down a 10% deposit and you have a 90% LTV mortgage; put down 25% and you have 75% LTV. LTV is the single biggest driver of the interest rate you are offered, because a lower LTV means the lender has more of a cushion if house prices fall and they ever need to repossess and sell.

The crucial point is that pricing does not improve smoothly, it improves in steps at each LTV band. Cross from 91% to 90%, or from 76% to 75%, and you can drop into a cheaper set of products. That is why finding even an extra percent or two of deposit, just enough to tip you over a threshold, can be worth far more than the cash itself suggests.

It is worth understanding why lenders price this way. Your deposit is their margin of safety. If house prices fell and they ever had to repossess and sell a home, a borrower with a 40% deposit leaves them comfortably covered, while one at 95% offers almost no cushion. The higher rate on a high-LTV mortgage is the lender pricing in that extra risk, and it is also why a large deposit protects you from the risk of negative equity, where the loan is worth more than the home. That protection is easy to overlook when rates are the headline, but it matters if you ever need to sell in a soft market.

The deposit bands that matter

Because rates step at each band, it is worth knowing where the thresholds sit. The table below is illustrative, using a £250,000 home, but the pattern holds at any price: the more you put down, the cheaper the borrowing, with the biggest gains coming as you move away from the highest LTVs.

Notice how the benefit tapers. The jump from 5% to 15% transforms your options; the jump from 25% to 40% shaves far less off the rate. For most buyers the sweet spot is reaching the highest band they comfortably can without draining every last reserve, because, as we will see, the deposit is not the only cash you need at completion.

Buying with a small deposit

A 5% deposit is a perfectly legitimate way onto the ladder, and for many buyers the alternative is years more renting. But it is worth understanding the trade-offs honestly rather than discovering them later.

There is no universally right answer. Someone paying high rent in a rising market may be better off buying at 95% now than waiting; someone with a stable, cheap living arrangement may gain more by holding on and saving into a better band. It is a genuine trade-off between time and cost, and a regulated adviser can help you weigh it against your own circumstances: this is information, not personal advice, and house prices can fall as well as rise.

Gifted deposits and family help

A large share of first-time buyers now rely on family, and lenders are well used to it. A gifted deposit from close family is widely accepted, provided the giver signs a short letter confirming the money is a genuine gift, with no repayment expected and no stake in the property. The lender will also verify the source of the funds as part of routine anti-money-laundering checks, so build in a little time for that paperwork.

Where a relative wants to help but cannot or does not want to give cash away, a family-assist structure may fit better. Guarantor, springboard and joint borrower deals let a family member lend their savings or income instead of gifting a lump sum, and a regulated broker can explain how each one works and shares the risk. For larger gifts, it is also worth being aware that money given away can interact with inheritance tax under the seven-year rule if the giver dies within that window.

How to build a deposit faster

If you are still saving, the account you use matters as much as the amount you put in. Two government-backed and tax-efficient wrappers stand out for would-be buyers, and a few habits make the target far easier to hit.

• 1

  Open a Lifetime ISA

  Save up to £4,000 a year and the government adds a 25% bonus, up to £1,000 annually, towards a first home worth £450,000 or less. You must hold the account for 12 months before you buy.

• 2

  Use your ISA allowance

  You can shelter up to £20,000 a year across ISAs. A cash ISA keeps a shorter-term deposit fund safe from tax on interest, which matters as savings rates have risen.

• 3

  Automate the saving

  A standing order into your deposit pot on payday, before you can spend it, is the simplest way to make steady progress without willpower.

• 4

  Aim for the next band

  Rather than a round number, target the deposit that tips you over the next LTV threshold: the rate saving can outweigh the extra you set aside.

A word of caution on where you hold the money. A deposit you will need within a year or two is usually best kept in cash savings rather than invested, because investments can fall as well as rise and you do not want a market dip to shrink your deposit just as you are ready to buy. Weighing saving against other goals, such as clearing expensive debt, is the kind of question where broader planning helps; our overview of what financial advice costs sets out the typical fees involved.

One practical trap catches out plenty of savers: the Lifetime ISA’s rules. The 25% bonus is generous, but if you buy a home above the £450,000 price cap, or withdraw the money for anything other than a first home or retirement before age 60, you pay a 25% government charge on the amount taken out, which can leave you with less than you put in. It is an excellent tool used within its limits, but it pays to know those limits before you lock money away, especially if you are buying in a higher-priced area.

Costs beyond the deposit

Finally, resist the temptation to pour every last pound into the deposit. Buying a home carries costs that land at or near completion, Stamp Duty Land Tax where it applies, legal and conveyancing fees, a survey, and moving costs. Emptying your savings to squeeze into a better LTV band, only to have nothing left for these, is a common and avoidable mistake.

A sensible plan funds the deposit and a realistic budget for these extras, plus a small cushion for the unexpected. A whole-of-market adviser can model the full cash requirement and point you to the lenders best suited to your deposit and circumstances. You can find a vetted mortgage adviser in Truro, elsewhere through the mortgage advice network, and the matching service is free to use.

Common questions on mortgages