A payroll service typically costs in the region of £4 per employee, per month, for a small business with fewer than 10 employees. However, you should expect to pay more if you have a larger business with more people working for you. For example, a large business with complex payroll needs could spend up to £12 per employee for advanced payroll services each month. The cost of a payroll service also depends on how much you require of the company. The majority of payroll companies will provide a fixed quote for a monthly service.