Pro Rata Salary Calculator 2026/27

Calculate the proportional salary for a part-time employee based on days or hours worked per week.

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Full-time annual salary

Calculation mode

Full-time days per week

Actual days per week

Full-time hours per week

Actual hours per week

Pro-rata annual salary

£32,000

4 days / 5 days × £40,000

Full-time salary

£40,000

Pro-rata (annual)

£32,000

Monthly

£2,667

Weekly

£615

% of FTE

80.0%

Pro-rata calculation is proportional. Statutory benefits (pension, holiday) are also pro-rated.

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Frequently Asked Questions

How is pro-rata salary calculated?

Pro-rata salary is calculated by dividing the full-time salary by the full-time working hours or days, then multiplying by the actual hours or days worked. For example, if a full-time salary is £40,000 for 5 days per week and an employee works 4 days, their pro-rata salary is £40,000 × (4 ÷ 5) = £32,000.

Are statutory rights pro-rated for part-time workers?

Yes. Part-time workers are entitled to the same statutory rights as full-time workers on a pro-rata basis. This includes holiday entitlement, sick pay, pension contributions and redundancy pay. The Part-time Workers (Prevention of Less Favourable Treatment) Regulations 2000 require equal treatment.

How does pro-rata affect employer NI and pension?

Employer NI and pension contributions are calculated on the pro-rata salary, not the full-time equivalent. This typically reduces employer costs proportionally, though the lower qualifying earnings threshold means some low part-time salaries may attract less NI as a percentage.