1. 付款人；交款人
You can refer to someone as a payer if they pay a particular kind of bill or fee. For example, a mortgage payer is someone who pays a mortgage.

2. 支付人；还账人
A good payer pays you quickly or pays you a lot of money. A bad payer takes a long time to pay you, or does not pay you very much.

1. a person who pays money for something

Synonym: remunerator