Junior SIPP calculator
A childhood of contributions, a lifetime of growth
See what a Junior SIPP could be worth at retirement — including the government's 25% top-up, growing the whole way.
Your plan
The government adds 25%
Growth compounds monthly at your chosen rate — 6% is a deliberately conservative default. Contributions stop at 18; the pension keeps growing and is accessible from age 57 (rising to 58). Education, not financial advice — investments can go down as well as up.
Their pension at 67
£288,306
from 8 years of contributions that stop at 18
£57,661
of that is the government's top-up, grown
£961/month
retirement income (4% rule)
£15,354
pot at age 18
£9,600
all you ever pay in
A childhood of contributions, a lifetime of growth
Child's age
What does waiting cost?
Starting later means fewer contribution years and less time to grow.
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Ready to start building their future?
Squids-In helps families track Junior SIPP contributions and watch the government's free money grow.
Want money they can use at 18?
A Junior SIPP is locked until retirement. For university, a first home, or starting adult life, a Junior ISA hands over at 18 — many families run both side by side.
How Junior SIPP tax relief works
01
You contribute
Up to £2,880 per tax year of your own money — the "net contribution". Anyone can pay in: parents, grandparents, family.
02
The government adds 25%
Automatically, no tax return needed: £2,880 becomes £3,600. That £720 a year is real money, invested alongside yours.
03
Both grow for a lifetime
Contributions stop at 18, but nothing is withdrawn until retirement — giving compound growth 50+ years to work.
Frequently asked questions
Do I need to pay tax to get the 25% government bonus?
No! The 25% tax relief is added automatically to Junior SIPP contributions, even if you (or your child) don't pay any tax. It's truly free money from the government.
How much can I pay into a Junior SIPP each year?
The annual Junior SIPP allowance is £2,880 of your own money per tax year. The government automatically adds 25% on top, bringing the total invested to £3,600 a year.
Are Junior SIPP contributions tax deductible?
Not in the way a business expense is deductible — but you don't miss out. Instead of reducing your tax bill, the government adds 25% tax relief directly to the contribution: pay in £2,880 and it becomes £3,600 inside the pension. You get the relief even if you don't pay any income tax yourself.
Are dividends in a Junior SIPP tax free?
Yes. Dividends and interest earned inside a Junior SIPP are completely free of UK income tax, and any growth is free of capital gains tax. That tax-free compounding, running for 50+ years, is a big part of why the projections grow so large.
Is a Junior SIPP completely tax free?
Almost. Everything that happens inside the pension — growth, dividends and interest — is tax free, and the government adds 25% on the way in. The one exception is at retirement: 25% of the pot can be taken tax free, and the rest is taxed as income when your child eventually draws it (decades from now, under whatever rules apply then).
When can my child access their Junior SIPP?
Junior SIPPs can only be accessed from the minimum pension age (currently 57, rising to 58). That long lock-away is exactly why the projections are so large — the money has an entire lifetime to compound. Compare Junior ISA vs Junior SIPP.
How is the retirement income calculated?
We use the "4% rule" — a widely used guideline suggesting you can sustainably withdraw about 4% of a pension pot each year. So a £300,000 pot would provide roughly £12,000/year, or £1,000/month.
Why does starting early matter so much?
Every year you wait means one less year of contributions (they stop at 18) and one less year of growth on everything. Over a 50+ year horizon, even a one-year delay can cost tens of thousands — the calculator's cost-of-waiting section shows your own numbers.
Can I have both a Junior ISA and a Junior SIPP?
Yes! Many families use both — a Junior SIPP for long-term retirement savings (with the tax relief) and a Junior ISA for goals accessible at 18.
Learn more about Junior SIPPs
What is a Junior SIPP?
Everything you need to know about Junior Self-Invested Personal Pensions for children.
Read more →How Junior SIPP tax relief works
The complete guide to the 25% government bonus on Junior SIPP contributions.
Read more →Compare all account types
Junior ISA, Junior SIPP, savings accounts and Premium Bonds side by side.
Read more →