Cash ISA & Savings Growth Calculator UK
Forecast how your Cash ISA savings could grow — adjust initial investment, monthly contributions, period, and interest rate with sliders.
Switch to Compound Interest Saving for monthly or annual compounding projections.
Cash ISA & Savings Growth Calculator UK
How it works
- Choose Cash ISA Calculator or Compound Interest Saving
- Enter initial savings and monthly contributions
- Set interest rate, years, and compounding frequency
- Review year-by-year balance, milestones, and tax-free interest (Cash ISA mode)
Forecast how your ISA savings could grow. Adjust the sliders — we'll update your projection instantly.
Invest £5,000, add £200 a month for 10 years at 4.0%, and your Cash ISA could be worth:
£37,368
- Total contributed
- £29,000
- Interest earned
- £8,368
These projections are examples, not a guarantee of future returns.
Figures shown aren't guaranteed. Actual returns depend on interest rates, account terms, tax, and your personal circumstances. This calculator doesn't consider inflation or charges and isn't financial advice.
How this Cash ISA calculator works
- All cash, including interest earned, stays in the ISA for the full period.
- The interest rate stays the same for the whole period.
- Monthly contributions stay the same amount throughout.
- Interest is compounded annually using the annual rate.
Grow your savings with UK accounts
Compare ISA, savings, and investing options before choosing a provider.
UK Finance Support Guides & Calculator Hub
Result Explanation
This calculator page is available even when the content worker is offline. Use the inputs below to estimate UK finance scenarios and compare related tools.
Comparison Examples
- Compare different inputs before making a decision.
- Compare the result with realistic UK provider terms.
FAQ
Question: Can I use this calculator without the content worker?
Answer: Yes. The core calculator UI can load with fallback content while the worker service is unavailable.
How calculations work
Calculators use clear inputs such as amount, rate, term, tax year, contribution, or monthly payment. The support guides explain those inputs so users can understand the result.
Updated for UK context
Content is written for UK finance searches, including UK tax years, lending terms, ISA rules, APR, and repayment assumptions.
Financial assumptions explained
These pages are educational estimates, not financial advice. Users should compare provider terms and official rules before acting.