Calculate your FIRE number, see how long until you reach financial independence, and explore Lean, Fat, and Barista FIRE strategies for the UK.
How much you spend per year (not income)
ISA + pension + other investments
How much you invest per month
Before inflation (7% is typical for equities)
4% is standard. Use 3.5% for extra safety on 40+ year horizons.
Your FIRE Number
£750,000
4% withdrawal rate
Years to FIRE
20.5
At £1,000/month, 7% returns
Remaining
£700,000
Still needed to reach FIRE
Illustrative estimate only. Actual returns vary. Does not account for inflation, taxes, or market volatility.
| Type | Annual spending | FIRE number (4%) | Description |
|---|---|---|---|
| Lean FIRE | £15,000–£20,000 | £375k–£500k | Frugal lifestyle. Modest housing, minimal luxuries. Achievable on average salary with discipline. |
| Regular FIRE | £25,000–£35,000 | £625k–£875k | Comfortable UK lifestyle. Covers housing, holidays, and moderate discretionary spending. |
| Fat FIRE | £40,000–£60,000+ | £1M–£1.5M+ | Premium lifestyle. No financial compromises. Requires high income or long accumulation period. |
| Barista FIRE | Portfolio covers 60-70% | 50-70% of full number | Part-time work bridges the gap. Freedom to choose enjoyable, low-stress work. |
| Coast FIRE | N/A (still working) | Varies by age | Enough invested that compound interest alone reaches your FIRE number by 60-65. No more saving needed. |
The UK has unique advantages for FIRE pursuers. The Stocks & Shares ISA shelters £20,000 per year in tax-free investments, meaning a couple can shelter £40,000 annually. Over a 15-year accumulation period, that is £600,000 in tax-free capital. Combine this with workplace pension tax relief (20-45% depending on your bracket) and employer matching, and you have two powerful engines working simultaneously.
The optimal UK FIRE strategy typically follows this order: first, contribute enough to your workplace pension to capture the full employer match (this is an instant 60-100% return). Second, maximise your Stocks & Shares ISA (£20,000/year, all growth tax-free). Third, if you have additional capacity, increase pension contributions via salary sacrifice to benefit from National Insurance savings. Only after exhausting these tax-efficient wrappers should you use a general investment account.
One critical UK consideration: you cannot access your pension until age 57 (from 2028). If you plan to retire at 45, you need enough in your ISA and other accessible accounts to bridge the gap between early retirement and pension access age. The state pension (currently up to £11,502/year from age 67) further reduces your long-term FIRE number, a married couple receives up to £23,004/year from the state alone.
Your savings rate, the percentage of take-home pay you invest, is the single most important variable in reaching FIRE. Income matters less than most people think. A person earning £40,000 and saving 50% reaches FIRE far faster than someone earning £80,000 and saving 10%, because the high saver simultaneously builds their portfolio faster AND proves they can live on less (meaning a lower FIRE number).
| Savings rate | Years to FIRE | Notes |
|---|---|---|
| 10% | ~40+ years | Standard retirement timeline |
| 20% | ~30 years | Comfortable pace, retire at 55 if starting at 25 |
| 30% | ~22 years | Achievable with dual income, no lifestyle inflation |
| 40% | ~17 years | Requires intentional frugality or high income |
| 50% | ~14 years | The classic FIRE target. Live on half, invest half. |
| 60% | ~11 years | Aggressive. Usually requires high income + low costs. |
| 70% | ~8 years | Extreme frugality or very high earner |
Assumes 7% returns, 0% inflation, starting from £0. Real timelines depend on starting portfolio, returns, and expenses.
Forgetting about the pension access gap. If you retire at 45, your pension is locked until 57. You need 12 years of living expenses in accessible accounts (ISA, GIA). Many FIRE planners underestimate this bridge fund.
Ignoring the state pension. The full new State Pension is £11,502/year per person. A couple receives £23,004. This meaningfully reduces the portfolio you need from age 67 onwards. Factor it into your calculations, it effectively replaces £287,550 of portfolio (at 4% SWR) per person.
Using nominal returns instead of real returns. If your portfolio returns 7% and inflation is 2.5%, your real return is 4.5%. Plan using real returns, or your purchasing power will decline in retirement. Use our inflation-adjusted calculator to see the real picture.
Neglecting healthcare and insurance costs. Early retirees lose employer-provided benefits. Budget for private health insurance, income protection during the accumulation phase, and dental/optical costs. These can add £2,000-5,000/year to your expenses.
Step 1: Track your spending. You cannot calculate your FIRE number without knowing your annual expenses. Track every pound for 3 months. Most people discover they spend 20-30% more than they thought.
Step 2: Calculate your FIRE number. Use the calculator above. Multiply your annual expenses by 25 (for a 4% SWR). This is your target portfolio value.
Step 3: Maximise your savings rate. The gap between income and expenses is everything. Cut the big three: housing (downsize, house hack, or relocate), transport (cycle, use public transport, or buy used), and food (cook at home, meal prep). These three categories typically account for 60-70% of spending.
Step 4: Invest tax-efficiently. Employer pension match first, then max ISA (£20,000/year), then salary sacrifice pension, then GIA. Keep costs low, a single global index fund at 0.1-0.2% per year is all you need. Avoid active funds, trading fees, and financial advisers who charge percentage-based fees on your portfolio.
Step 5: Stay the course. FIRE is a decade-long project. Markets will crash, life will intervene, and motivation will waver. Automate your investments, check your portfolio quarterly (not daily), and focus on the variables you control: savings rate and career income.
Start your FIRE portfolio tax-free
Trading 212 · Free ISA · No commission · Start from £1
Get weekly investing tips & calculator updates
Free, no spam. Unsubscribe anytime.