Date of Service

50.4.4 - Date of Service (Rev. 66, Issued: 01-07-11, Effective: 02-08-11, Implementation: 02-08-11) The date of service (DOS) is the date a provider renders service to a beneficiary. Unless otherwise specified, the effective date of a change request is the date of service. For the purpose of processing claims, the effective date for applying processing rules, laws, processes, and/or policies is the date the beneficiary received a service from a provider. For Durable Medical Equipment (DME) claims with spanned dates of service, the ViPS Medicare System (VMS) will use only the “From” DOS as the date the supplier rendered a service to a beneficiary. For example, if a new rule or law became effective on January 1, 2011, and a beneficiary received service on December 27, 2010, then that service would not be covered under the new rule. If the beneficiary received the service on or after January 1, 2011, then that service would be covered by the new rule. More service-specific information on the Date of Service can be found in. Pub.100-02, Medicare Benefit Policy Manual and Pub. 100-04, Medicare Claims Processing Manual.