This early retirement calculator shows how much you need to save to retire before state pension age. Enter your current age, existing savings, monthly contributions and desired retirement income to find out whether you are on track — and what you would need to change if not.
Savings target & projection
The core question is: how large does your investment pot need to be so that you can live off it without running out of money? The most widely used framework is the 4% rule, which says you can safely withdraw 4% of your portfolio in year one, adjusting for inflation each year, with a high probability of lasting 30+ years.
That means your target pot is 25 times your desired annual income. Want £30,000 a year? You need £750,000. Want £40,000? You need £1,000,000. The calculator projects whether your current savings and contributions will reach that target by your chosen retirement age.
The 4% rule comes from the "Trinity Study" (1998), based on US stock and bond market data from 1926 to 1995. It found a 95% success rate for a 50/50 stock-bond portfolio over 30 years. For UK-based FIRE retirees, some considerations differ:
Longer time horizons. Retiring at 45 or 50 means needing your pot to last 40 to 50 years, not 30. A more conservative 3% to 3.5% withdrawal rate (33x or 29x income) may be safer for very early retirees.
Tax efficiency. Withdrawals from pensions are taxed as income, while ISA withdrawals are tax-free. Planning which accounts to draw from in which order can significantly extend your pot. Typically, use ISAs first (pre-pension age), then pension (post-57), then state pension (post-66).
Private pensions cannot normally be accessed before age 55 (rising to 57 from April 2028). If you retire at 45 or 50, you need non-pension assets to fund the bridge years. This means ISAs, general investment accounts (GIAs), rental income, or other passive income.
| Retirement age | Bridge years (to pension at 57) | Bridge years (to state pension at 67) |
|---|---|---|
| 45 | 12 years | 22 years |
| 50 | 7 years | 17 years |
| 55 | 2 years | 12 years |
For the bridge period, the ISA calculator shows how much tax-free savings you can build within the £20,000 annual allowance.
The full new state pension for 2026/27 is £230.25 per week (about £11,973 per year). This arrives at state pension age (currently 66, rising to 67 by 2028). Once it starts, it reduces the amount you need to withdraw from your private savings, extending their lifespan.
Check your state pension forecast at gov.uk/check-state-pension. If you retire very early, you may have gaps in your NI record — consider buying voluntary NI years to secure the full amount.
The 4% rule is a starting point, not gospel. Many FIRE planners use variable withdrawal strategies: withdrawing less in market downturns and more in good years. The "guardrails" approach sets an upper and lower limit (for example 3.5% to 5%) and adjusts spending accordingly. This significantly reduces the risk of running out of money while allowing you to enjoy good years.
Another approach is the bucket strategy: keep 1-2 years of expenses in cash, 3-5 years in bonds, and the rest in equities. This prevents you from selling shares during a crash, giving the equity portfolio time to recover.
The pension drawdown calculator models how long your pot lasts in drawdown. Use the compound interest calculator to project investment growth under different scenarios, and the pension vs ISA calculator to compare the two wrappers side by side.
A common rule of thumb is the 4% withdrawal rule, which suggests you need a pot of 25 times your desired annual income. For example, to withdraw £30,000 per year you would need a pot of £750,000. This assumes a diversified portfolio returning above inflation over the long term. The exact amount depends on your age at retirement, life expectancy and investment returns.
FIRE stands for Financial Independence, Retire Early. It involves saving and investing a high proportion of income, typically 50% to 70%, to build a portfolio large enough to cover living expenses indefinitely. The idea is to reach financial independence at 40 to 55 rather than the traditional state pension age of 66 to 68.
Private pensions cannot normally be accessed before the minimum pension age, which is 55 currently and rises to 57 from April 2028. For early retirement before this age, you need non-pension savings such as ISAs, general investment accounts, or other income sources to bridge the gap until your pension becomes accessible.
The 4% rule suggests you can withdraw 4% of your portfolio in the first year of retirement, then adjust for inflation each subsequent year, with a high probability of your money lasting at least 30 years. It is based on US historical market data. Some UK planners recommend a more conservative 3% to 3.5% rate given lower expected returns and longer retirement periods for FIRE retirees.
The full new state pension is £230.25 per week (2026/27), or about £11,973 per year. This kicks in at state pension age, currently 66, rising to 67 by 2028 and 68 in due course. You can factor this into your plan — once state pension starts, you need less from your private savings.
Both have a role. Pensions offer tax relief on contributions but are locked until age 55 or 57. ISAs are tax-free on growth and withdrawal with no access restrictions, making them ideal for the bridge period before pension age. A combination strategy uses ISAs for early years and pensions for later, maximising tax efficiency across your retirement.
A diversified global equity portfolio has historically returned around 7% to 8% per year before inflation, or 4% to 5% after inflation. The calculator uses your input — a 5% to 6% nominal return is a reasonable middle ground for long-term planning. Higher assumptions risk overestimating your pot, so err on the conservative side.
