How do you prorate an independent contractors monthly retainer fee?

To prorate an independent contractor's monthly retainer fee, first determine the daily rate by dividing the total monthly fee by the number of days in the month. Then, multiply the daily rate by the number of days the contractor provided services during that month. This calculation gives you the prorated amount owed for their work. Adjustments can be made if the contract specifies different rates for partial months or specific services.