Free learning guide • US revenue cycle
How US Medical Billing Works
Medical billing is the administrative process of turning documented healthcare services into claims, payments and reconciled accounts. The revenue cycle starts before the claim is sent and continues until balances are resolved.
Published October 15, 2026 · Educational reference, not payer-specific advice
In one minute
The typical workflow is registration → insurance verification → documentation and coding → charge entry → claim submission → adjudication → payment posting → denial and accounts-receivable follow-up. A claim can be accepted by a clearinghouse but still denied by a payer.
Eight practical steps in the claim lifecycle
STEP 1
Patient registration and coverage
Capture correct demographics, insurance identifiers, the intended date of service and the relevant payer. Use the 270/271 eligibility transaction or payer tools when available. A successful eligibility response does not necessarily guarantee payment.
STEP 2
Documentation and coding
Translate clinical documentation into supported diagnosis and procedure codes, modifiers and appropriate place-of-service information. Clinical documentation must substantiate the reported services and payer-specific requirements still apply.
STEP 3
Charge entry and claim preparation
Build the claim with patient, provider, diagnosis, service-line and billing identifiers. Professional claims often use the CMS-1500/837P context; institutional claims typically use UB-04/837I.
STEP 4
Claim edits and transmission
Validate claim fields, complete required edits and send the claim directly or through a clearinghouse using an appropriate electronic transaction, commonly ASC X12 837. A clearinghouse acceptance does not mean the payer has approved the claim.
STEP 5
Payer adjudication and claim status
The payer evaluates coverage, contract terms, benefits, coding and other rules. Use payer portals or applicable 276/277 transactions to investigate pending claims. A payer denial is different from a clearinghouse rejection.
STEP 6
Remittance and payment posting
Use the payer explanation of benefits or ASC X12 835 electronic remittance advice to match allowed amounts, payments, adjustments and patient responsibility to each claim and service line.
STEP 7
Denial management and AR follow-up
Classify the issue, investigate the adjustment and remark codes, correct billing errors where appropriate, request reconsideration or submit an appeal within the applicable payer timeline.
STEP 8
Reconciliation and reporting
Reconcile payments and contractual adjustments, review aged receivables, identify avoidable denials, and monitor recurring issues so the same errors are less likely to recur.
Electronic transaction reference
| Transaction | Common purpose |
|---|---|
| 270 / 271 | Eligibility inquiry and response |
| 837 | Electronic claim submission |
| 276 / 277 | Claim status inquiry and response |
| 835 | Electronic remittance advice and adjustment details |
For official standards, consult the Centers for Medicare & Medicaid Services (CMS) Adopted Standards and Operating Rules and Payment and Remittance Advice guidance.
Where beginners should focus
Start by understanding coverage and benefits, correct claim identifiers, the difference between claim rejection and payer denial, and how allowed amounts flow into remittance posting. Practice with synthetic examples—never real patient information in a public learning environment.
Continue with our RCM metrics guide, the Medical Billing Foundation syllabus, or contact admissions to ask about practical cohorts.