Working a back week is very common, yet there is very little information about it. 3 Questions: Q1. When you leave a job and get paid extra for the back week, at what salary do you get paid the back week? Is it at your final salary, your initial salary or and average salary? Q2. What rate of tax do you pay against the back week, is it taxed using the current tax rates or those in use at the time the week was worked? Q3. Given that your employer essentially owed you this money for the duration of your employment, are you entitled to be paid interest on it?