CPT 99357 with E&M Services

CPT-4 Code 99357 To report prolonged inpatient E&M services, CPT-4 codes 99357 (each additional 30 minutes) must be billed in conjunction with code 99356.

Billing Calculations CPT-4 codes 99356 and 99357 are subject to the least restrictive frequency limitation as the required companion code. To calculate the amount of time that is payable for prolonged inpatient services, take the total unit/floor time and subtract the time of the primary E&M service. The following table may be used to calculate billing for prolonged inpatient E&M services.

Time of E&M visit code not included                  First hour               Each additional 30 minutes

Less than 30 minutes                                       Not reported               Not reported

30 – 74 minutes                                               99356                        Not reported

75 – 104 minutes                                             99356                        99357

105 – 134 minutes                                           99356                       99357 (quantity of 2)

135 – 164 minutes                                           99356                       99357 (quantity of 3)

165 – 194 minutes                                          99356                        99357 (quantity of 4)