You may have a prorated salary when you are contracted to work for a specific number of days but do not actually work for that many days. Your salary would then be proportional to the number of days you actually worked; this means that if you worked half as many days as the contract is for then you would be paid half as much. To calculate your prorated salary, you will need to know how many days the contract is for, how many days you actually worked, and your contract salary.
Divide your salary by the number of days you were contracted to work to get your pay per day. As an example, take a contract for food service at a college, that is £27,300 for 200 days of work. The contractor, however, is hired a month into the school year and thus will work only 175 days. £27,300 / 200 = £136 / day.
Multiply your salary per day by the number of days you will actually work to get your gross salary for the year. Continuing the example: £136 / day x 175 days = £23,887.
Count the number of paydays remaining in the contract. Divide your gross salary by the number of paydays to get your gross salary for each paycheck. Finishing the example: the contract pays twice a month and there are seven months remaining, which means 14 paychecks. £23,887 / 14 = £1,706 per paycheck.
Salaries may also be prorated if you there is a change in your salary.