LISA Bonus Calculator
The Lifetime ISA is one of the best deals in UK personal finance: the government adds 25p for every £1 you put in, up to £1,000 free money per year. This calculator shows how that bonus compounds over time versus a plain ISA.
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Eligibility
Must be aged 18–39 to open. Can contribute until age 50.
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First home use
Property must be ≤ £450,000. Must hold the LISA for 12+ months first.
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Withdrawal penalty
Taking money out for any other reason incurs a 25% penalty — you lose bonus and ~6% of your own money.
Your numbers
Your annual LISA bonus
Bonus advantage
£11,088
more than a plain ISA after 10 years, thanks to the 25% top-up
After 10 years
Includes £7,500 in government bonuses
Same contributions, no government top-up
Total you contributed
£30,000
Total bonus received
£7,500
Year-by-year
| Year | LISA | Plain ISA | Bonus gain |
|---|---|---|---|
| 1 | £4,013 | £3,210 | +£803 |
| 2 | £8,306 | £6,645 | +£1,661 |
| 3 | £12,900 | £10,320 | +£2,580 |
| 4 | £17,815 | £14,252 | +£3,563 |
| 5 | £23,075 | £18,460 | +£4,615 |
| 6 | £28,703 | £22,962 | +£5,741 |
| 7 | £34,724 | £27,779 | +£6,945 |
| 8 | £41,167 | £32,934 | +£8,233 |
| 9 | £48,062 | £38,449 | +£9,613 |
| 10 | £55,438 | £44,351 | +£11,087 |
Assumptions & notes
- Contributions are capped at the £4,000/year government limit (£333/month).
- The 25% bonus is applied to your annual contribution at the start of each year.
- Both the LISA and the plain ISA comparator grow entirely tax-free.
- No withdrawal penalty is modelled — this shows the full-bonus scenario.
- To use a LISA for a first home, the property must cost no more than £450,000 and you must have held the account for at least 12 months.
- This is an illustration only, not financial advice.