Calculating Earnings

Earnings are net earnings after deducting tax and National Insurance. Except for income support and housing benefit, you can also deduct any expenses of working including travel, 19 p towards a meal, and anything else which is reasonable and incurred because of the work. If you work occasionally or irregularly, your earnings are counted for the period to which they relate.

For example, if you do one day's work and get one day's pay, you cannot average the amount out over a longer period.

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or Working After Pension Age

National Insurance

/retirement/pensions/income/national-insurance.php... see: National Insurance