How the 25% penalty actually works
The arithmetic trips people up because the penalty applies to the withdrawal amount, not the contribution.
You put in £4,000. The government adds £1,000 (25% bonus). Your LISA holds £5,000. If you make an unauthorised withdrawal, HMRC charges 25% of the total — that's 25% of £5,000 = £1,250.
You get back £3,750. You put in £4,000. You've lost £250 of your own money — a 6.25% haircut on what you saved.
Scale that up. Five years of maximum £4,000 contributions with no growth gives you £25,000 in the LISA (£20,000 yours + £5,000 bonus). An unauthorised withdrawal costs £6,250 in penalties. You walk away with £18,750 — £1,250 less than you saved.
The temporary Covid-era reduction to 20% (which preserved your capital) ended on 6 April 2021. The penalty is back to its full, punitive 25%.
According to HMRC guidance on Lifetime ISAs, the withdrawal charge applies to any amount taken out for a non-qualifying purpose. There is no partial exemption. Terminal illness is the only hardship exception — redundancy, divorce, or financial distress do not qualify for penalty-free access.
The maths gets worse if your LISA is invested in stocks and shares rather than cash. Market losses compound with the penalty. If your £5,000 LISA drops 10% to £4,500 and you then face the 25% withdrawal charge, you receive just £3,375 — a 15.6% loss on your original £4,000 contribution.