What is a Lifetime ISA?
A Lifetime ISA is a tax-free savings account designed for two specific goals: buying your first home or saving for retirement. You can contribute up to £4,000 per year and receive a 25% government bonus — that's free money, up to £1,000 per year. The LISA is open to anyone aged 18–39; once opened, you can contribute until age 50. All growth inside the LISA is completely tax-free, just like any ISA.
The catch is that your LISA contributions count against your overall £20,000 annual ISA allowance (shared across Stocks & Shares ISA, Cash ISA, etc.). And if you withdraw money for any reason other than first home purchase or age 60+, you lose 25% of the amount you take out — which actually means you lose some of your own money, not just the bonus.
The 25% bonus: free money with strings attached
For every £4 you contribute to your LISA, the government adds £1. This bonus is paid monthly, so if you contribute £333 per month (£4,000 per year), you receive £83.25 per month in bonus. Over 20 years, that 25% boost compounds into a substantial pot — but only if you keep the money until age 60 or use it for a qualifying first home purchase.
If you withdraw your money early (not for a first home and not at age 60+), you face a 25% withdrawal penalty. This isn't just on the bonus; it's on your entire pot. So a £5,000 withdrawal triggers a £1,250 penalty, leaving you with just £3,750 — you've given back not just the bonus but also lost 6.25% of your own contributions plus the growth on the bonus. This makes early withdrawal very expensive.
The £450k cap and the withdrawal penalty
For first home purchases, your property must be under £450,000. This is a hard cap. If you're buying a property over £450k, you cannot use your LISA at all — you lose eligibility for the bonus, cannot withdraw for the purchase, and if you try to withdraw, you face the full 25% penalty. This is why checking the price cap is the first step in any first home LISA plan.
The 25% penalty applies to the entire withdrawal amount, not just the bonus. Withdraw £10,000 at age 45 for any non-qualifying reason, and you pay £2,500 in penalty. You receive £7,500. This makes the LISA illiquid by design — it's a serious long-term commitment.
LISA vs Help to Buy ISA vs SIPP: when each one wins
Lifetime ISA wins if: You're aged 18–39 buying a first home under £450k within 1–5 years, or you're saving for retirement and want simplicity. The 25% bonus is genuinely generous — it beats any employer match outside of pension salary sacrifice.
Help to Buy ISA wins if: You're older than 39 and saving for your first home. There's no LISA option past 39, but the old Help to Buy ISA still exists for eligible savers with no age limit. The bonus is only 25% up to £1,000 on £16k, so £4,000 total pot. It's smaller than LISA but better than nothing.
SIPP wins if: You're a higher-rate taxpayer saving for retirement. A SIPP gives you tax relief on contributions (so you net 33p tax back on every pound), and you get a 25% tax-free lump sum at retirement. But you can't touch the money until 55 (rising to 57 by 2028). For early retirement (before 60), LISA is more flexible. For retirement after 60 with a good income, SIPP tax relief usually wins.
Your inputs
Year-by-year growth
This table shows how your LISA pot accumulates, including the monthly government bonus paid alongside your contributions.
| Year | Contributions | Bonus | Growth | Balance |
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When a LISA beats a SIPP
A basic-rate taxpayer (20%) saving £2,000 into a LISA each year receives a 25% bonus, netting £2,500 invested. A SIPP at 20% relief gets £2,000 gross from contributions, with only 20% tax relief — so the taxpayer invests £1,600 of their own money to get £2,000 gross. Over 20 years at 5% growth, the LISA's 25% boost often wins for early retirement (before 60) and offers complete flexibility at 60 (no age limit, unlike pension drawdown minimum ages).
But the SIPP wins if: (a) you're a higher-rate taxpayer (40% relief, so £2,000 contribution is heavily subsidised), (b) your employer matches contributions (free money), or (c) you're saving for retirement beyond age 65 and want to maximise tax-free withdrawals and manage your lifetime allowance. For most basic-rate savers aged 25–40 targeting first home or early retirement, the LISA is simpler and usually more generous.
When a SIPP beats a LISA
Higher-rate and additional-rate taxpayers get 40% or 45% tax relief, which dramatically changes the maths. A £4,000 net contribution gets you £6,667 invested (at 40% relief). That bonus scales with your tax rate, far exceeding LISA's fixed 25%. Moreover, pensions offer no withdrawal penalty — you can access your pot at 55 (rising to 57) without losing a penny. For retirement, this flexibility plus relief is powerful.
The SIPP also avoids the £450k first home cap, allows unlimited contributions (unlike LISA's £4k annual limit and overall £20k ISA ceiling), and offers spouse relief and lifetime allowance management tools. If you earn over £50k, a SIPP almost always wins for retirement savings.
Common LISA mistakes
Opening after 39: You cannot open a LISA after age 39, though you can continue contributing until 50 if already open. Don't leave it too late — the early years of the 25% bonus compound significantly.
Buying over £450k: Many first-time buyers assume their LISA works with any property. It doesn't. Any property over £450,000 forfeits the bonus and eligibility. You lose 25% on withdrawal. Check the price cap before committing.
Withdrawing early: An unexpected financial emergency at age 35 may tempt you to raid your LISA. A 25% penalty means you lose both the bonus and some of your own money. Use the LISA only if you're confident you won't need access before 60 or your first home purchase.
Ignoring the ISA allowance: Your LISA counts as part of your £20,000 annual ISA limit. If you max out a LISA (£4,000), you have only £16,000 left for Stocks & Shares or Cash ISA. Plan your overall ISA strategy accordingly.