Hundred SummersLifetime ISA calculator: the bonus, and the honest penalty
Save up to £4,000 a year and the government adds 25%: free money for a first home or for age 60. The catch most pages soften: withdraw for anything else and the 25% charge takes back more than the bonus; 6.25% of your own money. This calculator prices both, on the same constants the Hundred Summers app's projection uses. Your figures never leave your browser.
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Worked example
Computed when this page was built by the same engine that runs the calculator above, so the figures below and the live tool can never disagree. Change any input above to see your own.
| Inputs | |
|---|---|
| Age | 28 |
| Paid in a year | £4,000 |
| Growth | 5.0% |
| Results | |
|---|---|
| Contributing years to 50 | 22 |
| Your contributions | £88,000 |
| Government bonus | £22,000 |
| Pot at 60 | £329,285 |
| Early withdrawal: kept per £1,000 | £750 |
| Loss of your own money on early withdrawal | 6.25% |
The next question
How long will a deposit take to save? →House deposit calculator
Or answer it with everything else: the full Hundred Summers plan connects your pay, pensions, savings, property, tax and spending year by year, and stress-tests them across 500 simulated market histories.
Read the guide
- ISA or pension? Where long-term money should go, and the Lifetime ISA's place →The same gross pay by two routes (pension with relief and a tax-free quarter, or ISA after tax and NI) compared on your rate now and in retirement, why the pension usually wins on tax and the ISA on access, and where the Lifetime ISA's 25% bonus fits.
Where the LISA fits
The LISA occupies a precise niche: first-home buyers who will spend under £450,000 (a cap frozen since 2017 while prices rose; check your market), and self-employed savers with no employer pension, for whom the 25% bonus is the only match they'll ever get. For employed basic-rate savers it's a strong second wrapper after pension matching is captured; for higher-rate earners, pension relief at 40%+ comes first.
The projection here uses the same limits the Hundred Summers app enforces (£4,000 a year, bonus while under 50, access at 60), so what you see is what a plan would actually do. Compare routes with the ISA vs pension calculator, and put the result inside a whole retirement picture with the how-much-to-retire calculator.