The short answer: We do not take credit card payments ourselves. We use a third party company to process the the payments and they charge the fee. The county does not receive any of the fee. That third party forwards the amount paid towards your property taxes to us and keeps the fee.
The longer answer: Historically, credit card companies had rules against charging for credit card payments (although this is changing). For example, a business could not charge a fee for using a credit card. Because of these rules, most government agencies do not accept credit cards because governments would not pay for the fees required to process the payments. The results of this started an industry of third party payment companies that act as a middle-man between someone doing business with a government agency and the agency itself. This link goes to one of those companies that we have partnered with to provide a convenient way to pay online via credit card. We would prefer to have a way to pay via credit card without a fee, but that is not possible at this time. That is one of the main reasons why we have worked so hard to provide another option, paying by check online for free, to make it easier to do business with our office.