Isaac - Retirement Planning

Will your money last in retirement? Isaac helps you find out. The UK's best retirement calculator.

Most pension tools give you a single number and hope for the best. Isaac models your complete retirement picture — DC pensions, DB pensions, State Pension, ISAs, savings, property, and your partner's finances — so you can see what's actually going on.

HOW IT WORKS

Plug in your pensions, savings, and spending. Isaac does the maths — monthly compounding, inflation, tax, the lot — and shows you year by year how your money holds up from retirement to age 100. Base case, optimistic, and pessimistic scenarios side by side.

TAX-EFFICIENT DRAWDOWN

This is where Isaac really earns its keep. It works out the smartest order to withdraw your money — filling your personal allowance with pension withdrawals first, then drawing from ISAs tax-free, then taking taxable withdrawals only when needed. You can see exactly how much tax you save each year compared to just pulling everything from your pension.

WHAT YOU CAN MODEL

- Multiple DC pensions with different growth rates

- DB (final salary) pensions with inflation linking

- State Pension based on your NI qualifying years

- ISAs, cash savings, and other investments — tracked separately

- Partner planning with independent pensions and tax

- Contribution changes at any age

- Spending phases — different levels through retirement

- Property sales, downsizing, and equity release

- One-off costs at any age (new car, home repairs, care fund)

- Extra income (rental, part-time work, side income)

- Annuity purchase, flexi-access drawdown, or a blend of both

- Discretionary spending reduction in later life

SCENARIO PLANNING

What if I retire at 58 instead of 62? What if I increase contributions by £200 a month? What if I downsize at 70? Create multiple scenarios and compare them side by side. Free users get one basic scenario. Premium unlocks unlimited scenarios and all features.

BUILT FOR UK PENSIONS

Isaac uses UK tax bands (England, Wales, and Scotland), the lump sum allowance cap, current State Pension rates, and inflation-adjusted thresholds. It's designed for people with UK workplace pensions.

YOUR DATA IS PRIVATE

Your financial data is encrypted and stored securely. Isaac doesn't sell your data, show you ads, or try to sell you financial products. It's a planning tool, not a sales funnel.

FREE TO START

Sign up and build your first scenario for free. Upgrade to Isaac Premium for unlimited scenarios, partner planning, tax-efficient drawdown modelling, and all advanced features.

Premium subscription:

- Payment is charged to your Apple ID account at confirmation

- Subscription automatically renews unless cancelled at least 24 hours before the end of the current period

- Manage in Settings > Apple ID > Subscriptions

Terms of Use: https://www.isaacmoney.com/terms

Privacy Policy: https://www.isaacmoney.com/privacy

Isaac provides projections for planning purposes only. It does not provide financial advice. Projections are based on assumptions that may not reflect actual outcomes. If you need advice, speak to a qualified financial adviser.