The Plastiq bill payment service offers a convenient way to pay bills with a credit card for a 2.5% fee. Unfortunately, there are a few restrictions. In June of this year, Visa stopped allowing Plastiq to accept Visa cards for mortgage payments. And now Amex has done the same.
After I received a reader tip (thanks Tom), I reached out to Plastiq and they confirmed: customers will have to “use a Mastercard or Discover to pay mortgage.”