Income protection is offset against everything else that pays

The points below about benefit offsets are ordered by how much difference they make, not by how often they get repeated.

Why a ceiling exists at all

Insurers cap income protection benefit at a proportion of pre-incapacity earnings rather than replacing income entirely. The reasoning is straightforward: nobody should be financially better off unable to work than working normally.

That principle shapes the whole product, from the maximum benefit to the treatment of other income during a claim. The proportion allowed differs between insurers and markets, and it is often tiered so higher earners are covered at a lower rate. Tax treatment also matters, since benefits paid free of tax in some systems are capped at a lower proportion of gross earnings to reflect the difference.

What usually counts against the benefit

Employer sick pay running alongside a claim is normally deducted, which is one reason deferred periods matter so much. Other individual income protection policies are counted, so holding two rarely produces two full benefits. Group schemes provided by an employer are counted, and they are frequently generous enough to absorb the whole allowance.

State incapacity or disability benefits are deducted by many policies, though practice differs considerably by country. Some policies also count continuing investment or pension income, and others deliberately ignore it.

The over-insurance trap

Someone who buys the maximum benefit and later joins an employer with a generous scheme may be paying for cover that cannot pay. The premium continues, but the benefit at claim is reduced to fit the ceiling once other income is counted.

In practice, insurers do not automatically refund the difference, because you bought the cover and it was available if circumstances differed. This is one of the strongest arguments for reviewing protection whenever your employment arrangements change. It is also why a policy bought while self-employed needs revisiting after taking a salaried role.

Fixed and guaranteed benefit versions

Some policies pay a stated amount without reference to earnings at the time of claim, which removes the calculation uncertainty. These are often more expensive, and the amount available is usually capped at a lower level for that reason.

They suit people whose income is irregular, hard to evidence or likely to fall shortly before a claim. Others assess earnings at the point of claim, which can penalise anyone whose income dropped in the preceding period. Which approach a policy uses is stated in the wording and is one of the most consequential details in it.

Proving earnings when self-employed

Self-employed claimants must evidence income, usually from accounts or tax filings over a recent period. Where earnings fluctuate, insurers may average several years, which can produce a figure well below a recent good year.

Put simply, business expenses, drawings and retained profits are treated differently by different insurers, so definitions matter. A business that continues generating income while you are ill can reduce the benefit under some wordings. Keeping clean, consistent records is the practical protection here, since the claim is assessed on filed documents rather than on your own description of a normal year.

Adjust the size of it until it is something you would actually do tired.

Keeping the cover aligned

Recalculate the maximum benefit whenever your income changes materially, in either direction. Check what your employer provides, since group cover is often the largest single offset and is easily forgotten. Ask the insurer how state benefits are treated in your country, because this varies more than any other offset.

On an ordinary week, consider whether a fixed benefit structure suits an irregular income better than an earnings-linked one. These are financial decisions specific to your circumstances, so take regulated advice rather than acting on general information.

Everything above, in order of what to do first

1. Why a ceiling exists at all. Insurers cap income protection benefit at a proportion of pre-incapacity earnings rather than replacing income entirely.
2. What usually counts against the benefit. Employer sick pay running alongside a claim is normally deducted, which is one reason deferred periods matter so much.
3. The over-insurance trap. Someone who buys the maximum benefit and later joins an employer with a generous scheme may be paying for cover that cannot pay.
4. Fixed and guaranteed benefit versions. Some policies pay a stated amount without reference to earnings at the time of claim, which removes the calculation uncertainty.
5. Proving earnings when self-employed. Self-employed claimants must evidence income, usually from accounts or tax filings over a recent period.
6. Keeping the cover aligned. Recalculate the maximum benefit whenever your income changes materially, in either direction.

The takeaway

Add up every source that would pay while you were ill, then insure the gap rather than the whole salary.

Pick the one that costs you least, and let the rest wait.