Occurrence Codes

Note: Any codes not listed within this table are not currently in use by CMS. This includes any code ranges that are considered Reserved for National Assignment.

Code Description Additional Information
01 Accident/Medical Coverage Code indicating accident-related injury for which there is medical payment coverage. Provide the date of accident/injury.
02 No Fault Insurance Involved - Including Auto Accident/Other Date of an accident, including auto or other, where the State has applicable no-fault or liability laws (i.e., legal basis for settlement without admission or proof of guilt).
03 Accident/Tort Liability Date of an accident resulting from a third party's action that may involve a civil court action in an attempt to require payment by the third party, other than no-fault liability.
04 Accident/ Employment Related  
05 Accident/No Medical or Liability Coverage Code indicating accident related injury for which there is no medical payment or third-party liability coverage. Provide date of accident or injury.
06 Crime Victim  
09 Start of Infertility Treatment Cycle  
10 Last Menstrual Period  
11 Onset of Symptoms/Illness Outpatient claims only. If beneficiary receiving a combination of PT/OT/SLP only one 11 occurrence code is required.
12 Date of Onset for A Chronically Dependent Individual  
16 Date of Last Therapy Code indicates the last day of therapy services (e.g., physical, occupational or speech therapy).
17 Date Outpatient Occupational Therapy Plan Established or Last Reviewed  
18 Date of Retirement - Patient/Beneficiary  
19 Date of Retirement - Spouse  
20 Date Guarantee of Payment Began Part A hospital claims only. Date hospital begins claiming payment.
21 Date Ur Notice Received  
22 Date Active Care Ended Date a covered level of care ended in SNF or general hospital or date active care ended in psych or tuberculosis hospital or date patient was released on trial basis from residential facility. *Code not required if code "21" is used.
23 Payer Code Date of Cancellation of Hospice Election Period. For FI Use Only. Providers Do Not Report. *Not required if code 21 is used.
24 Date Insurance Denied  
25 Date Benefits Terminated by Primary Payer  
26 Date SNF Bed Became Available Date SNF bed available to the Inpatient who requires only SNF level care.
27 Date of Hospice Certification or Recertification  
28 Date Comprehensive Outpatient Rehabilitation Plan Established or Last Reviewed  
29 Date Outpatient Physical Therapy Plan Established or Last Reviewed  
30 Date Outpatient Speech Pathology Plan Established or Last Reviewed  
31 Date Beneficiary Notified of Intent to Bill (Accommodations) Beneficiary does not (or no longer) require covered level of inpatient care.
32 Date Beneficiary Notified of Intent to Bill (Procedures or Treatments) Is not reasonable or necessary under Medicare.
33 First Day of The Coordination Period for ESRD Beneficiaries Covered By EGHP Required only for ESRD beneficiaries.
34 Date of Election of Extended Care Facilities Used by Religious Non-medical Health Care Institutions only.
35 Date Treatment Started for Physical Therapy  
36 Date of Inpatient Hospital Discharge for Covered Transplant Patient NOTE: When patient received a covered and non-covered transplant, the covered transplant predominates.
37 Date of Inpatient Hospital Discharge for Non-Covered Transplant Patient  
38 Date Treatment Started for Home IV Therapy  
39 Date Discharged on a Continuous Course of IV Therapy  
40 Scheduled Date of Admission This code may only be used on an outpatient claim.
41 Date of First Test for Pre-Admission Testing This code may be used only if date of admission was scheduled prior to administration of test(s).
42 Date of Discharge Hospice discharge due to patient revocation.
43 Scheduled Date of Canceled Surgery  
44 Date Treatment Started for Occupational Therapy  
45 Date Treatment Started for Speech Therapy  
46 Date Treatment Started for Cardiac Rehabilitation Beneficiary must have regular coinsurance and/or lifetime reserve days available beginning on this date to allow coverage of additional daily charges to receive cost outlier payments.
47 Date Cost Outlier Status Begins  
48 Payer Code  
49 Payer Code  
50 Assessment Date (Effective 1/1/11) Assessment Date for IRF, SNF and SB PPS. Note: Not required for SNF HIPPS code AAAxx
51 Date of Last Kt/V Reading (Effective 7/1/10)  
52 Medical Certification/Recertification Date (Effective 1/1/11)  
54 Physician Follow-Up Date (Effective 1/1/11)  
55 Date of Death (Effective 10/1/12)  
56 Original Hospice Election or Revocation Date (Effective 1/1/18)  
61 Hospital Discharge Date (HHA Only) (Effective 1/1/20)  
62 Other Institutional Discharge Date (HHA Only) (Effective 1/1/20)  
A1 Birthdate - Insured A Birth date of insured in whose name the insurance is carried.
A2 Effective Date - Insured A Policy First date insurance is effective.
A3 Benefits Exhausted - Payer A Last date benefits are available and no payment can be made by Payer A.
A4 Split Bill Date Date patient became Medicaid eligible due to medically needy spend down.
B1 Birthdate - Insured B  
B2 Effective Date - Insured B Policy  
B3 Benefits Exhausted - Payer B  
C1 Birthdate - Insured C  
C2 Effective Date - Insured C Policy  
C3 Benefits Exhausted - Payer C  
DR Reserved for Disaster Related Occurrence Code  


Last Updated Dec 09 , 2023