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What is a Pro Rata Salary?
A pro rata salary is the proportion of a full-time salary that an employee earns for working part-time. It's a common arrangement in the UK for part-time workers, job shares, and term-time only positions. The principle is that pay should be fair and proportional to the hours worked compared to a full-time equivalent.
How is Pro Rata Salary Calculated in the UK?
The standard method for calculating a pro rata salary in the UK involves three key figures: the full-time annual salary, the employee's contracted weekly hours, and the standard full-time weekly hours for the role. The calculation is typically done in two steps.
First, you find the full-time hourly rate by dividing the full-time annual salary by the total number of hours a full-time employee works in a year (full-time weekly hours multiplied by 52 weeks).
Second, you multiply this hourly rate by the employee's own contracted weekly hours and then by the number of weeks they work per year. For employees who work all year round, this is 52 weeks. For term-time only staff, it is the number of weeks they are contracted and paid to work.
Example Calculation
Let's say a role has a full-time salary of £30,000 for 37.5 hours per week, all year round. An employee is hired for 22.5 hours per week.
- Full-time hourly rate: £30,000 / (37.5 hours/week * 52 weeks) = £30,000 / 1,950 hours = approximately £15.38 per hour.
- Pro rata salary: £15.38/hour * 22.5 hours/week * 52 weeks/year = £17,994.60 per year.
This employee would earn a pro rata salary of about £17,995 annually.
Term-Time and Other Adjustments
For term-time workers, the calculation adjusts for the number of weeks worked. If a teaching assistant has a full-time equivalent salary of £28,000 for 35 hours per week, but only works 30 hours per week for 39 weeks a year, the calculation is:
- Hourly rate: £28,000 / (35 * 52) = £15.38.
- Pro rata salary: £15.38 * 30 * 39 = £17,994.60.
Even with different inputs, the proportional pay is calculated fairly based on time worked.
Frequently Asked Questions About Pro Rata Pay
Are part-time workers entitled to the same benefits?
Yes, under UK law, part-time workers have the right to not be treated less favourably than comparable full-time workers. This applies to pay rates, pension schemes, holiday entitlement (calculated pro rata), and access to training.
How is pro rata holiday calculated?
Holiday entitlement for part-time workers is also calculated pro rata. The statutory minimum is 5.6 weeks of paid holiday per year. For a part-time worker, this means 5.6 times their usual working week. For example, someone working 3 days a week is entitled to 16.8 days of paid holiday (5.6 * 3).
Can my employer use a different calculation method?
Employers can use other methods as long as they are fair, transparent, and do not discriminate. Some may calculate salary based on a daily rate or use an annualised hours contract. The key is that the outcome should be proportionally fair compared to a full-time colleague.
Next Steps: Formalising Your Employment Terms
Once you have calculated your expected pro rata salary, it's important to have the terms formally documented. For a new position, an Offer of Employment Letter should clearly state the pro rata salary, contracted hours, and working weeks. This is followed by a full Employment Contract which legally outlines all terms and conditions of your employment. If you are an existing employee requesting a change to part-time hours, a Letter to Request Flexible Working is the appropriate first step to formally propose your new working pattern.