The C&MA has an agreement with tithe.ly, with some lower negotiated fees. More information available here.
PayPal.Me is another service which is similar in price and some churches have started using.
Encourage Members to Look Into On-Line Bill Pay: Congregants should check to see if their banks offer a “Bill Pay” option. They can set up the church as a regular payment they make, and the bank generates an electronic check and sends it via USPS (United States Postal Service). Many banks don’t charge for this, and some even cover the postage!