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Salary Sacrifice Guides

Practical guides to salary sacrifice pensions, tax relief, and NI savings.

Salary sacrifice is the most tax-efficient way most employees can pay into a pension, and also the most misunderstood. The mechanism is simple enough: you formally give up part of your gross salary and your employer pays that amount into your pension instead. Because the money never counts as your earnings, neither you nor your employer pays National Insurance on it.

That NI saving is what separates salary sacrifice from an ordinary pension contribution. A normal contribution gets income tax relief but still has employee NI deducted first. A sacrifice avoids both, which is why the same pension outcome costs you noticeably less from take-home pay.

The employer saves too, at the employer NI rate, and many pass some or all of that saving back into your pension. Where they do, the effective return on sacrificing is higher again. Whether yours does is worth asking, because it is often the single largest variable in the calculation.

The trade-offs are real but narrow: your stated salary falls, which matters for mortgage affordability, death-in-service cover expressed as a multiple of salary, and a small number of earnings-linked benefits. These guides cover both sides so you can judge whether the arrangement suits your circumstances rather than assuming it always does.

All guides

Using these with the calculators

Read the guide that matches your question, then put your own salary and contribution rate through the calculators to see the actual figures. The numbers move a lot depending on which side of the higher rate threshold you sit and whether your employer shares its NI saving, so a worked example using your own inputs is far more useful than a general rule.

Two things worth checking before you increase a sacrifice. You cannot sacrifice below the National Minimum Wage, which caps what lower earners can do. And a sacrifice is a contractual change rather than a payroll setting, so it usually cannot be reversed at will, only at points your scheme allows or on a qualifying life event.

Jump straight to a tool: pension calculator, salary sacrifice calculator or the employer NI saving calculator.

General information, not financial advice. Pension and tax rules change, and the right level of contribution depends on your wider circumstances. Consider regulated advice before making significant changes.