HealthCare News

Onset/Occurrence Date

Issue: #398 DEC2017

Topic: Coding/Billing


To help eliminate denied claims and reduce the number of requests for additional information, the Date of Current Illness or Occurrence Code and associated date should be included when submitting claims. Keep in mind the date of service is not always the onset/occurrence date. Claims will process differently depending on the date entered.

On the CMS-1500 claim form, the Date of Current Illness (also known as the onset date) is entered into Box 14 to indicate the first date of onset of illness, the actual date of injury or the last menstrual period (LMP) for pregnancy. If the patient has had the same or similar illness previously, that date is entered into Box 15.

On the UB-04 claim form, the Occurrence Code and associated date are entered in Form Locators 31-36 and define a significant event related to the claim. Common occurrence codes are listed below.

Occurrence codeDefinition
01Accident/Medical Coverage
02No Fault Insurance Involved, Including Auto Accident/Other
03Accident/Tort Liability
04Accident/Employment Related
05Accident/No Medical or Liability Coverage
10Last Menstrual Period (LMP)
11Onset of Symptoms/Illness
13First Day of the Coordination Period for End Stage Renal Disease (ESRD) Beneficiaries Covered by EGHP