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New to Isaac, or to planning? These two get you going.
App guide · About 15 minutes
How to use Isaac, step by step
Every screen, input and result in the app: getting started, adding pensions, reading the dashboard, comparing plans, and planning as a couple.
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How long will my money last?
Enter your pot, spending and State Pension and see the age your money runs out, year by year, with UK tax applied.
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Pensions
What you have, how it grows, and what it will pay.
GuideDefined contribution pensionsHow DC pots grow: contributions, tax relief, allowances and investment choices.
GuideDefined benefit pensionsFinal salary and career average schemes, revaluation, and swapping pension for cash.
GuideThe UK State PensionHow much you’ll get, qualifying years, deferring, and the triple lock.
ArticleState Pension explainedWhat you’ll receive, checking your National Insurance record, and filling gaps.
Taking your money
Turning pots into income, with as little tax as the rules allow.
GuideTax-free cash (PCLS and UFPLS)Taking your 25% tax-free: all at once, bit by bit, or a mix of the two.
GuideDrawdown strategiesFlexible drawdown, annuities, and making the money last.
ArticleShould I take my 25% tax-free lump sum?All at once, a slice with every withdrawal, or not yet: what each one gives up.
ArticleHow much income tax will I pay in retirement?A worked example for 2026/27: what £2,500 a month after tax costs before tax.
ArticleRetiring before your State PensionSizing the gap from 58, 60 or 62 to 67, and which money to spend first.
ArticleThe 4% rule in the UKWhere the rule came from, and why it travels badly to the UK.
How much you need
Your number, how safe it is, and the big decisions along the way.
ArticleHow much do I need to retire?The Retirement Living Standards, the rules of thumb, and how to find your own number.
ArticleHow safe is my retirement plan?Sequence-of-returns risk, and two ways to stress-test a plan.
ArticlePlanning retirement as a coupleTwo incomes, two tax allowances and two State Pension dates, planned as one household.
GuideFIRE planning in the UKRetiring early: bridging the years to pension age, and ISA laddering.
ArticlePay off the mortgage or pay into the pension?A worked example for 2026/27 of where spare money does more.
ArticleDownsizing to fund retirementStamp duty, moving costs and the other numbers people forget.
Tax and inheritance
What the tax rules take, and what you leave behind.
GuideInheritance tax basicsNil-rate bands, gifts, taper relief, and the 2027 pension changes.
ArticleInheritance tax explainedThresholds, exemptions, and ways to reduce an inheritance tax bill.
ArticlePensions and inheritance tax from April 2027Unused pensions start to count towards your estate: what changes, and what to think about.
ArticleUK fiscal drag explainedInteractive charts of 40 years of frozen thresholds, and what they cost you.
Your situation
Guides for particular jobs and circumstances.
GuideBusiness owners: retained profits to retirementPension contributions, dividends, a members’ voluntary liquidation or a sale: the tax on each in 2026/27.
GuideCivil Service Pensioners’ AllianceCSPA membership, pension increases, McCloud, and the Alpha and PCSPS schemes.
ArticleRetirement planning for pilotsThe age-65 limit, the gap before State Pension, and stress-testing your plan.
Public-sector pension?
Scheme-by-scheme guides with 2026/27 rules.
NHS
Teachers’
LGPS
Civil Service
Police
Firefighters
Armed Forces
All public-sector guides