What are 837 and 835 transactions?
How healthcare claims and remittances move between providers and payers, in plain language.
In U.S. healthcare, providers and insurers exchange billing data using HIPAA X12 transactions, a set of EDI formats required under HIPAA's administrative simplification rules. The two you'll hear about most are the 837 and the 835.
The 837: the claim
An 837 is a health care claim. A provider (or their billing company) sends it to a payer to request payment for services. There are three main variants:
| Variant | Used for |
|---|---|
| 837P | Professional claims, such as physician office visits |
| 837I | Institutional claims, such as hospital stays |
| 837D | Dental claims |
ST*837*0001*005010X222A1~
BHT*0019*00*CLM20261104*20261104*1030*CH~
NM1*85*2*LAKESIDE FAMILY CLINIC*****XX*1234567893~
NM1*IL*1*DOE*JANE****MI*W123456789~
CLM*PT1001*185***11:B:1*Y*A*Y*Y~
HI*ABK:J069~
SV1*HC:99213*185*UN*1***1~
DTP*472*D8*20261103~
SE*9*0001~The 835: the remittance
An 835 is the electronic remittance advice. The payer sends it back to explain what was paid, what was adjusted and why. Billing teams use 835s to post payments and find denials to work.
The rest of the family
| Transaction | What it does |
|---|---|
| 270 / 271 | Eligibility inquiry and response: is this patient covered? |
| 276 / 277 | Claim status request and response: where is this claim? |
| 278 | Prior authorization and referral requests |
| 999 / 277CA | Acknowledgments that a file or claim was received and accepted |
Where does a clearinghouse fit?
Most providers don't connect to each payer directly. A clearinghouse routes transactions to and from many payers. A translation layer, like the one we're building with CareFlo, sits on your side: it turns these transactions into clean data your systems can use, validates them before they're sent, and tracks them. Payer connectivity is arranged separately.
More guides: What is EDI? · The supplier's guide to retail EDI documents
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