First Iteration:
Loop 2310A, NM1 (Referring Provider Name)
NM101 = DN (to indicate Referring Provider)
NM108 = 24 (Employer’s Identification Number)
Or
NM108 = 34 (Social Security Number)
NM109 = Employer’s Identification Number or Social Security Number
And
Loop 2310A, REF (Referring Provider Secondary Identifier)
REF01 = 0B (to indicate State License Number preceded by License type)
          = 1D (to indicate Medicaid Provider ID)
REF02 = Referring Provider Secondary Identifier

Second Iteration (if applicable):
Loop 2310A, NM1 (Referring Provider Name)
NM101 = P3 (to indicate Primary Care Provider)
NM108 = 24 (Employer’s Identification Number)
Or
NM108 = 34 (Social Security Number)
NM109 = Employer’s Identification Number or Social Security Number
And
Loop 2310A, REF (Referring Provider Secondary Identifier)
REF01 = 0B (to indicate State License Number preceded by License type)
          = 1D (to indicate Medicaid Provider ID)
REF02 = Referring Provider Secondary Identifier

(Professional only) For Ordering Provider (DME)
Loop 2420E, NM1 (Ordering Provider Name)
NM101 = DK (to indicate Ordering Physician)
NM108 = 24 (Employer’s Identification Number)
Or
NM108 = 34 (Social Security Number)
NM109 = Employer’s Identification Number or Social Security Number
And
Loop 2420E, REF (Ordering Provider Secondary Identification)
REF01 = 0B (to indicate State License Number preceded by License type)
          = 1D (to indicate Medicaid Provider ID)
REF02 = Ordering Provider Secondary Identifier