Can I get a refund if I reduce the number of seats in my company?

If you are on a monthly contract: 

If you downsize mid-month, you will be billed at the new rate the following month. 

If you are on an annual contract: 

Annual contracts are pre-paid for a specified number of seats. If an employee  leaves your company, their seat remains active (and could be filled by a new hire at no additional cost). Customers cannot reduce the number of seats until the end of the annual contract.