Glossary.
Every financial term used across MoneyMap, the Planner, and this website, explained simply — no assumed background required.
Coast FI
The point where you've saved enough that, left alone to grow, your pension/investments would reach a comfortable retirement without you adding another penny. You'd still work if you wanted to — just not because you had to.
Safe Withdrawal Rate (SWR)
The percentage of your savings you could spend each year in retirement with a very low risk of running out. 4% is the most commonly used starting point — it's a guideline, not a guarantee.
Safety buffer / emergency fund
Cash kept easily accessible for the unexpected — a job loss, a broken boiler — so a shock doesn’t force you into debt. Usually measured in months of essential costs, commonly 3–6.
SIPP
Self-Invested Personal Pension — a pension you control yourself, choosing your own investments, as opposed to a workplace pension managed on your behalf. Same tax rules and access age as other personal pensions.
Stocks & Shares ISA (S&S ISA)
A UK investment account where any growth is completely tax-free. You can pay in up to £20,000 per tax year (2026/27), and — unlike a pension — you can access the money any time, at any age.
Pension tax relief
The government adds money to your pension when you contribute, as an incentive. For a basic-rate taxpayer, pay in £80 and £100 lands in your pension — the government adds the other £20. Higher and additional-rate taxpayers can claim back even more, though the extra usually has to be claimed via Self Assessment rather than added automatically.
Annual allowance (pensions)
The most you can pay into a pension in one tax year and still get tax relief on it — £60,000 for most people in 2026/27, or 100% of your earnings if that's lower. It shrinks for very high earners.
PAYE
Pay As You Earn — the system that takes Income Tax and National Insurance directly out of a regular salary before it reaches your bank account. If you're on PAYE, your tax is already handled for you.
Self-employed / off-the-top tax
If you're self-employed, nothing is deducted automatically — you're paid the full amount and are responsible for setting tax aside yourself before spending the rest. MoneyMap calls this an “off-the-top” rule.
HMRC
His Majesty’s Revenue and Customs — the UK government department that collects tax.
Essentials-first (MoneyMap)
A way of labelling an income source in MoneyMap that tells it: pay the household’s fixed bills from this money before anything else happens to it.
AER
Annual Equivalent Rate — the standard way UK savings accounts show interest, letting you compare accounts fairly regardless of how often each one actually pays interest.
Compound interest
Interest earned on interest you've already earned, not just on your original amount — the reason money left invested tends to grow faster the longer it's left alone.
Runway (cash runway)
How many months your current savings would cover your essential costs if your income stopped completely today.
Net vs. gross
Gross is the amount before tax and deductions. Net is what actually lands in your account afterwards — the number that matters for day-to-day budgeting.
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