Guide

Disadvantages of Salary Sacrifice 2026/27

Published by the UK Money Calculators editorial team. Last updated for the 2026/27 tax year.

Salary sacrifice is one of the most tax-efficient ways to save for retirement. But it is not without drawbacks. Before increasing a sacrifice — or starting one — understand the potential downsides. For most employees the benefits outweigh the risks, but the disadvantages are real and can matter in certain circumstances.

1. Mortgage affordability

Mortgage lenders base how much they will lend on your income. Most use your contractual gross salary as the starting point. Many will use the post-sacrifice salary on your payslip, not the pre-sacrifice figure.

If you earn £50,000 and sacrifice £5,000, your post-sacrifice contractual salary is £45,000. A lender offering 4.5x income would lend £202,500 rather than £225,000 — a £22,500 difference that could affect what you can buy.

Approaches vary by lender:

  • Some lenders add back the pension sacrifice when calculating affordability, treating your income as the pre-sacrifice figure.
  • Others use the lower post-sacrifice salary without adjustment.
  • A mortgage broker familiar with lender criteria can identify which lenders are most accommodating for high-sacrifice arrangements.

If you are planning a mortgage application, consider temporarily reducing your sacrifice beforehand to maximise the income figure.

2. State pension entitlement

State Pension entitlement is based on NI contribution records — specifically whether you have qualifying years. You earn a qualifying year when your earnings are at or above the Lower Earnings Limit (LEL), £6,396 for 2026/27 (£123/week).

If your post-sacrifice salary falls below the LEL you stop accumulating qualifying years. For most full-time employees this is not a risk — even a big sacrifice leaves earnings well above £6,396. But it matters for:

  • Part-time workers on lower salaries who sacrifice a high proportion of income
  • Employees very close to minimum wage levels

As long as post-sacrifice earnings stay above the LEL, State Pension entitlement is fully preserved. The amount of NI paid above the LEL doesn't affect whether you get the qualifying year.

3. Defined benefit pension schemes

In a DB pension scheme, your pension is based on "pensionable pay" multiplied by years of service and an accrual rate. If your employer defines pensionable pay as the post-sacrifice salary, sacrificing into a DC arrangement could reduce the pensionable pay figure used to calculate your DB pension.

Some DB schemes explicitly exclude sacrifice amounts and calculate benefits on the pre-sacrifice salary. Others don't. Check your scheme rules or ask your pension administrator before sacrificing if you are a DB member. Reducing DB accrual for a short-term NI saving may not be worth it.

If your scheme defines pensionable pay as pre-sacrifice earnings, you are fine. But always verify rather than assume.

4. Life assurance and death-in-service benefits

Employer-provided life assurance typically pays a multiple of salary, commonly 2x to 4x. If the policy defines "salary" as the post-sacrifice contractual figure, the payout to your dependants could be lower than expected.

A £60,000 employee with £5,000 sacrifice may have cover based on £55,000. At 4x that pays £220,000 rather than £240,000.

Check your employer's life assurance documentation. Some explicitly use the pre-sacrifice figure; others don't. If the policy uses the lower figure, consider additional personal life cover to bridge the gap.

5. Income protection insurance

Employer-provided income protection typically pays 50–75% of salary if you cannot work due to illness or injury. If the policy is based on post-sacrifice salary, your benefit will be proportionally lower.

The same issue as with life assurance. Review your income protection policy and ask whether the reduced payout would be enough if you couldn't work for a sustained period.

6. National Minimum Wage

Salary sacrifice cannot reduce your cash pay below the National Minimum Wage (NMW). For 2026/27, the main NMW rates are:

  • National Living Wage (age 21+): £12.21/hour
  • Age 18–20: £10.00/hour
  • Under 18 and apprentices: £7.55/hour

Employers are responsible for ensuring salary sacrifice doesn't breach NMW. If it would, the sacrifice must be capped or refused. Employees on variable hours or earning close to NMW should check before agreeing to any sacrifice. See the Salary Sacrifice and Minimum Wage guide for more detail.

This is an employer compliance issue. But if your employer offers a sacrifice that would breach NMW, they cannot legally process it.

7. Means-tested benefits and income-linked calculations

Some financial calculations are based on adjusted net income — your income after deducting pension contributions. Salary sacrifice and personal pension contributions both reduce adjusted net income, so salary sacrifice provides no extra benefit over a personal contribution for these purposes. Areas where this matters:

  • Student loan repayments: Calculated on gross earnings above the threshold. Salary sacrifice reduces gross pay, so it does reduce student loan repayments — this may be a benefit or a consideration depending on your loan balance and repayment strategy.
  • Child Benefit high income charge: Calculated on adjusted net income. Salary sacrifice reduces this, which may help you avoid or reduce the charge if your income is between £60,000 and £80,000.
  • Tax-Free Childcare eligibility: Both parents must earn under £100,000 adjusted net income. Salary sacrifice can help keep income below this threshold.
  • Personal allowance tapering: If your income exceeds £100,000, the personal allowance tapers at £1 for every £2 over — effectively creating a 60% marginal rate. Salary sacrifice reduces adjusted net income and can restore some or all of the personal allowance.

These interactions can make salary sacrifice more valuable in certain income ranges, not less. The net effect depends on your individual situation.

Try the calculator

See the income tax and NI saving from salary sacrifice — and weigh it against the considerations on this page — using our free calculator.

Open the calculator →

Frequently asked questions

Does salary sacrifice affect my mortgage?

It can. Many lenders calculate affordability based on your post-sacrifice salary rather than your pre-sacrifice salary, which could reduce the amount they are willing to lend. The impact varies by lender — some add back pension sacrifice when assessing income, others do not. If you are planning a mortgage application, speak to a broker and consider temporarily reducing your sacrifice before applying.

Does salary sacrifice reduce my State Pension?

Only if it reduces your post-sacrifice earnings below the Lower Earnings Limit (£6,396 for 2026/27). Provided your earnings remain above this threshold, your State Pension qualifying year is protected regardless of how much NI you actually pay above that level. For most full-time employees this is not a concern, but part-time workers or those close to minimum wage should check.

What happens if my salary is close to minimum wage?

Salary sacrifice cannot reduce your take-home pay below the National Minimum Wage. If your current salary is close to NMW, the amount you can sacrifice may be limited or zero. Your employer is responsible for ensuring the sacrifice does not breach NMW. If they offer a sacrifice that would breach NMW, they must refuse or cap it. See our minimum wage guide for more detail.

Could salary sacrifice reduce my death-in-service payout?

Possibly. If your employer's life assurance policy defines the covered salary as the post-sacrifice contractual salary, the payout multiple will be applied to the lower figure. Check your policy documentation or ask HR whether the policy uses pre- or post-sacrifice salary. If it uses the lower figure, you may wish to consider additional personal life cover.

Is salary sacrifice still worth it despite the disadvantages?

For most employees, yes — the income tax and NI savings are significant and the disadvantages can usually be managed or mitigated. The key is to be aware of the potential impacts before committing to a sacrifice level, particularly if you are planning a mortgage, in a defined benefit scheme, or earning close to minimum wage. If in doubt, a financial adviser can help you weigh the trade-offs.

Official sources

This guide is for general information only. It does not constitute financial, tax or legal advice. Tax rates and rules can change. Always check current GOV.UK guidance and consult a qualified adviser before making decisions.