UK Deposit Savings Calculator
Work out how long it will take to save a house deposit, and what a Lifetime ISA adds on top.
Last updated: 16 September 2026
Time to reach £30,000
3.3 years
Around December 2029
You put in
£19,500
Interest earned
£2,276
Lifetime ISA bonus
£3,250
Saving £100 more a month would get you there 5 months sooner.
🔒Calculated in your browser. Assumes a steady monthly amount and a fixed interest rate — real rates move around.
For most first-time buyers the deposit is the hard part, not the mortgage. This works out how long your current savings pace takes to reach the deposit you need, and how much difference a Lifetime ISA makes on top.
Frequently Asked Questions
How long does it take to save a house deposit?
It depends on the deposit size and how much you can put away. Saving £500 a month towards a £30,000 deposit takes about five years; £1,000 a month halves that. The calculator shows the exact time for your numbers, including interest.
What is a Lifetime ISA and is it worth it?
A Lifetime ISA (LISA) is a savings account for a first home. The government adds 25% on top of what you pay in, up to £1,000 a year. You can open one aged 18–39, and the property must cost under £450,000. If you use it just for the deposit, the bonus is effectively free money.
How much deposit do I need to buy a house in the UK?
The minimum is usually 5% of the property price, with 10% being the common target for first-time buyers. A bigger deposit gets you a lower interest rate, so 15% or 20% can save money over the life of the mortgage.
What if I save into a regular savings account instead?
You still earn interest, but you lose the 25% government bonus. Work out both ways above — for a first home, the LISA bonus usually beats a slightly higher interest rate, as long as the property is under £450,000.
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