payor vs payer are essentially the same, both referring to the individual or entity that makes a payment. While “payer” is more commonly used in general English and financial contexts, “payor” is often found in legal and healthcare documents. There is no practical difference in meaning; it's mainly a stylistic or industry-specific preference. For example, in healthcare, insurance companies are often called payors. In common banking or everyday financial use, “payer” is the standard term. Both terms function identically in usage and intent.