How is the pension pot calculated?

Employee + employer + tax-relief contributions are added to the existing pot each year, then the whole pot grows by the chosen rate. The calculator iterates year-by-year to retirement age.

What's a realistic growth rate?

Pension regulators in the UK and US typically use 2% real (after inflation) for cautious projections, 5% for balanced, and 7% for growth-focused funds. Past returns do not guarantee future performance.

Should I include tax relief?

For UK and Irish pensions yes — relief (20–45% UK, 20–40% Ireland) is grossed up by HMRC / Revenue on top of your contribution. For US 401k and EU pre-tax workplace pensions there is no separate relief — the contribution is already taken before income tax.

A common safe-withdrawal heuristic — withdraw 4% of the pot each year (rising with inflation) and the pot has historically lasted 30+ years. Newer research suggests 3.3–3.7% is safer in current low-yield conditions.

🌅 Pension Pot Calculator

Project your retirement pot with employer match and tax relief — UK pension or US 401k.

Scheme

Currency

Current age

Retirement age

Current pension pot

Annual salary

You contribute (% of salary)

Employer match (% of salary)

Tax Relief Band

Expected annual growth (%)

Annual salary growth (%)

⚠️ Not financial advice. Future returns are uncertain. Speak to a regulated financial adviser before making changes to your pension contributions.

About the Pension Pot Calculator

The Pension Pot Calculator projects your workplace pension or 401k forward to your chosen retirement age. It compounds employee + employer + (UK / Ireland) tax relief contributions through the years and applies your chosen growth rate. Three schemes are supported: UK pension, Ireland pension, and pre-tax (US 401k or most EU workplace pensions).

How tax relief works (UK)

For every £80 you contribute from take-home pay, HMRC adds £20 (basic-rate relief) — making the gross contribution £100. Higher-rate (40%) and additional-rate (45%) taxpayers can claim further relief via Self-Assessment. The calculator applies relief automatically when "UK pension" is selected.

How tax relief works (Ireland)

Irish Revenue applies relief at your marginal rate (20% standard or 40% higher) using the same gross-up mechanism as the UK. Age-banded contribution limits apply (15% of earnings under 30, rising to 40% at age 60+), and an earnings cap of €115,000 sits on top. The calculator does not enforce these caps — verify with Revenue.ie or a tax adviser.

Pre-tax pensions (US 401k and EU workplace)

US 401k contributions and most continental European workplace pensions (German bAV, French PER, Dutch 2nd pillar, Spanish planes de pensiones, Italian fondi pensione) are taken from pre-tax salary — your taxable income drops by the contribution amount, and no extra relief is added on top. Country-specific contribution caps apply (e.g. €1,500 individual cap in Spain, €5,164 in Italy, ~€3,624 of BBG-tax-free space for German bAV) and aren't enforced here. Pick this option for any pre-tax workplace pension.

The 4% rule

A widely-used heuristic for retirement income: withdraw 4% of the pot each year (rising with inflation), and the pot historically lasts 30+ years. Newer research after years of low yields suggests 3.3–3.7% is safer.

Frequently Asked Questions

Why is "today's money" lower than the nominal pot? Inflation erodes buying power. £1m in 30 years won't buy what £1m buys today. The calculator deflates the projected pot by 2.5% per year for a "real-terms" figure.

What growth rate should I use? Cautious: 2% real (≈ 5% nominal). Balanced: 4% real (≈ 7% nominal). Growth: 5–6% real. Real returns assume inflation of around 2.5%.

Should I include the State Pension? No — this calculator only models a workplace/401k pot. Add the State Pension or Social Security separately when planning total retirement income.

⚠️

Important Note: Projections are illustrative only. Capital is at risk and past performance does not guarantee future returns. Consult a regulated adviser before significant pension decisions.

Related Calculators

401(k) Calculator — US 401(k) projection with employer match, salary growth and 2026 IRS limits.
Retirement Goal Tracker — Are you on track? Projected pot vs. pot needed for your target income.
Social Security Calculator — Estimate your US Social Security benefit at 62, Full Retirement Age and 70.