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Contributions stop at 18, but nothing is withdrawn until retirement — giving compound growth 50+ years to work.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.
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 →