The short answer
Higher-rate or additional-rate taxpayer? SIPP, almost always. 40-47% upfront relief beats 25%.
Basic-rate taxpayer or non-taxpayer? LISA usually wins, especially if you're under 40 and either saving for first home OR not expecting your retirement income to be high. 25% bonus + tax-free withdrawals at 60 + first-time-buyer flexibility.
Both? Use both. The LISA's £4,000/year limit is independent of the SIPP's £60,000 annual allowance. Many people in their 30s use the LISA for the first £4,000 and the SIPP for the next £4,000–£40,000 of pension contributions.
The structural comparison
| Feature | LISA | SIPP |
|---|---|---|
| Government top-up / relief | 25% bonus on contributions up to £4,000/year | 20-47% relief depending on income tax band |
| Annual contribution limit | £4,000/year (counts toward £20,000 ISA limit) | £60,000/year (or 100% of earned income, whichever is lower) |
| Age you can open | 18-39 | Any age |
| Age you can contribute to | 18-49 (no contributions after 50) | Up to 75 |
| Earliest withdrawal | 60 (penalty-free) or first home (penalty-free) | 55 (rising to 57 in 2028) |
| Tax on withdrawals | Tax-free | 25% tax-free, 75% taxable as income |
| Penalty for non-qualifying early withdrawal | 25% (which on the bonus + your contribution amounts to ~6.25% loss of original contribution) | Marginal rate income tax + possible 55% additional charge |
| IHT treatment (current) | Inside estate | Outside estate (until April 2027 — changes thereafter) |
Worked example 1 — Basic-rate taxpayer, age 30, £4,000/year
£4,000/year contribution, 30 years, 5% net return.
- LISA route. £4,000 contribution + £1,000 government bonus = £5,000/year invested. After 30 years at 5%: £349,000. Withdrawn at 60, all tax-free.
- SIPP route. £4,000 contribution + £1,000 government top-up (20% gross-up) = £5,000/year invested. Same £349,000 after 30 years. At withdrawal: 25% tax-free (£87,250), 75% taxable as income (£261,750). If you can keep withdrawals within personal allowance and basic rate, average tax ≈ 15-18%, so net ≈ £296,000.
For a basic-rate taxpayer who'll be a basic-rate taxpayer in retirement, LISA wins by ~£50,000 over 30 years on this contribution level — purely because withdrawals are tax-free instead of partially taxable.
Worked example 2 — Higher-rate taxpayer, same £4,000/year
Same £4,000/year, but contributor is higher-rate.
- LISA route. Same as above: £5,000/year invested, £349,000 after 30 years, all tax-free at 60. Net cost over 30 years: £4,000 × 30 = £120,000.
- SIPP route — net of higher-rate relief. £4,000 contribution, plus £1,000 basic-rate gross-up at source, plus £1,000 reclaimed via Self Assessment. Net cost £3,000 per year. Same £349,000 after 30 years. Net cost over 30 years: £3,000 × 30 = £90,000.
So a higher-rate taxpayer pays £30,000 less for the same SIPP outcome vs the LISA. Even after retirement income tax (15-20% average), SIPP comes out comfortably ahead.
The first-home use case (LISA's killer feature)
The LISA is the only UK pension wrapper that lets you withdraw penalty-free for a first-home purchase. The conditions are tight but workable:
- Property under £450,000 (UK-wide, not London-specific).
- You haven't owned a UK property before.
- The LISA has been open for at least 12 months.
- You buy the property with a residential mortgage.
For a first-time buyer in their 20s or early 30s, the maths is unambiguous: contributing the £4,000 LISA limit each year delivers £1,000 of free government bonus per year. £20,000 over 5 years becomes £25,000 plus growth, which can clear half a typical first-home deposit.
The LISA calculator shows the bonus + growth path for any contribution scenario, and the first-time buyer guide covers the use of LISA as part of a deposit.
The death-benefit angle
Currently, SIPP balances pass to nominated beneficiaries outside the estate for IHT. LISA balances are inside the estate. For an ordinary middle-class household this difference is small, but for higher-net-worth households it has historically been one of the largest reasons to favour SIPPs.
From April 2027 (under current legislation), defined-contribution pensions are pulled into the estate for IHT. This narrows the gap — LISAs and SIPPs will be more similar on the death angle from then. The IHT guide covers the regime change.
Common mistakes
- Maxing the LISA without taking the employer pension match first. The employer match in a workplace pension is typically 3-6% of salary, free. That beats both LISA and SIPP relief. Take the match first, then choose between LISA / SIPP for any remaining contribution.
- Using the LISA for a non-qualifying withdrawal in your 30s/40s. The 25% penalty is on the value, not the contribution — you lose your bonus and a slice of your own money. Don't open a LISA if there's a meaningful chance you'll need the cash before 60 or first home.
- Forgetting the 50-year-old contribution cliff. You can't contribute to a LISA after age 50, and you can't open one after 40. SIPPs have neither restriction.
- Treating LISA as a 25% return on day one. It is, but only if you stay disciplined to 60+. Early withdrawal turns the 25% bonus into a 6.25% net loss on your original contribution.
Sources
GOV.UK — Lifetime ISA · Tax on your private pension · MoneyHelper — Lifetime ISA.