Medical Billing Process: 10 Steps From Visit to Payment

A practice can deliver excellent care and still struggle financially when billing breaks down. For example, a missing authorization, a mistyped member ID or a late claim can each cost the full payment for a visit. This guide walks through each step, the forms and electronic transactions involved, and the checks that keep claims clean.

What the medical billing process is

Medical billing is the work of preparing claims, sending them to payers, following up until they pay and then billing patients for their share. A medical biller uses the codes a coder assigns, builds the claim, sends it to the payer, usually through a clearinghouse, posts the payment and resolves denials.

Billing sits inside the wider healthcare revenue cycle, which also includes scheduling, front-desk checks and reporting. In other words, billing is the part of the cycle where claims are built and paid, while the steps around it decide whether those claims succeed.

The 10 steps of the medical billing process

Each step depends on the one before it. Therefore, a mistake early in the process tends to show up later as a rejection, a denial or a patient complaint.

1. Register the patient

Collect the patient’s legal name, date of birth, address and phone number. Then record the insurance details exactly as they appear on the card, including the subscriber and the patient’s relationship to that person. Scan the front and back of the card at every visit, because plans and member IDs change.

In addition, make key fields mandatory in your practice management system. A claim with a misspelled name or a wrong date of birth will not match the payer’s records, so it comes back as a rejection before anyone reviews it.

2. Verify insurance eligibility and benefits

Next, check that coverage is active on the date of service, that the provider is in network, and what the patient will owe as a copay, deductible or coinsurance. Then, for electronic checks, use the X12 270/271 eligibility inquiry and response. Also ask about a second plan, since the wrong payer order leads to coordination-of-benefits denials.

3. Obtain prior authorization and referrals

Then confirm whether the plan requires prior authorization or a referral for the planned service. If it does, record the authorization number, the approved codes, the number of units and the valid dates. A service performed outside those limits may not pay, even when the patient clearly needed it.

4. Document the encounter

During the visit, the provider documents the history, exam, medical decision making or time, and any procedures. The note has to support every code billed and show why the service was medically necessary. As a result, an incomplete note limits what the practice can bill, no matter how much work the provider did.

5. Capture charges

Then every billable service, supply and drug becomes a charge. Set an internal target for entering charges soon after the visit, such as within one to three business days, and track the gap. When charges wait, cash slows down and some services never reach a claim at all.

6. Code the services

Coders then translate the documentation into standard codes:

• CPT codes for procedures and services, such as 99214 for an established-patient office visit with moderate medical decision making.
• HCPCS Level II codes for supplies, drugs and some services.
• ICD-10-CM codes for diagnoses, at the highest specificity the note supports.
• Modifiers, such as 25 or 59, that explain special circumstances.

7. Scrub and submit the claim

Before submission, a claim scrubber checks the claim against payer rules and coding edits. Professional claims, for example, use the CMS-1500 format, sent electronically as the 837P. Institutional claims, however, use the UB-04, sent as the 837I.

A practice can send claims through a clearinghouse, which checks the format, routes each claim to the right payer and returns acceptance or rejection reports. For Medicare claims, check Medicare’s electronic billing and EDI requirements for the formats and transactions it accepts.

8. Track the claim and post payments

After submission, check claim status with the X12 276/277 transaction or the payer portal. Once the payer decides, it sends an ERA (electronic remittance advice, the X12 835 file) or a paper EOB. The billing team then posts payments, contractual adjustments and patient responsibility to each line and reconciles the total with the bank deposit.

9. Work denials and follow up on unpaid claims

When the payer denies a line, the remittance shows reason and remark codes, such as CO-16 for missing information or CO-97 for a bundled service. Billers then correct and resubmit the claim, or appeal it, within the payer’s deadline. They also follow up on any claim that stays unpaid past the expected payment window instead of waiting for it to age.

Deadlines matter here. Under the federal timely filing rule for Medicare claims, a claim must be filed no later than one calendar year after the date of service, with a few narrow exceptions. Commercial and Medicaid limits vary by payer and contract, so keep a list for each payer you bill.

10. Bill the patient and collect the balance

Finally, once insurance pays, the patient receives a clear statement for any deductible, coinsurance or non-covered service. Offer online payment and payment plans, send statements on a consistent schedule and answer billing questions quickly. Patients pay sooner when the bill matches what they were told at check-in.

Documents and transactions at each step

In addition, several standard forms and electronic transactions move information between the practice, the clearinghouse and the payer. The table below shows where each one fits.

Item	What it is	Step
270/271	Electronic eligibility inquiry and response	2
278	Electronic prior authorization request and response	3
Superbill or encounter form	List of the services and codes for one visit	5–6
CMS-1500 / 837P	Professional claim for physicians and clinics	7
UB-04 / 837I	Institutional claim for hospitals and facilities	7
276/277	Claim status inquiry and response	8
835 (ERA) / EOB	Payment, adjustment and denial details from the payer	8–9

Example: one visit from check-in to payment

Here is a hypothetical example of an established patient seen for diabetes and high blood pressure.

1. At scheduling, the front desk runs an eligibility check, confirms the plan is active and notes a $30 copay.
2. At check-in, staff scan the card, confirm the address and collect the copay.
3. The physician documents the visit, adjusts a medication and closes the note the same afternoon.
4. The charge reaches billing the next morning, and a coder assigns the visit code and two diagnosis codes.
5. The scrubber flags no errors, so the claim goes out through the clearinghouse that day and the payer accepts it.
6. Two weeks later, the ERA shows the allowed amount, the payment and a small coinsurance balance. The poster applies it and moves the balance to the patient.
7. The patient receives one statement and pays it online.

Now change one detail: the patient switched plans and nobody re-checked eligibility. In that case, the old plan denies the claim, the team has to find the new plan and resubmit, and payment slips by weeks. That single skipped check at step 2 affects every later step.

Medical billing vs. medical coding

Coding translates the documentation into standard codes, while billing uses those codes to create claims, get paid and collect balances. In a small practice, one person may do both jobs. In larger groups, the roles tend to split, so coders can focus on accuracy and billers can focus on payment and follow-up.

Even so, the two teams need to talk. For example, when a payer denies a claim for a coding reason, the biller should send it back to the coder rather than change the code alone. Our medical coding services work alongside billing for this reason.

Common errors in the medical billing process

Billing problems tend to repeat, which means a practice can prevent them once it knows where they start. Watch for these errors:

• Wrong or missing patient or insurance details at registration.
• Coverage that ended, or a second plan nobody recorded.
• Services performed without a required authorization.
• Codes the note does not support, or missing modifiers.
• Duplicate claims sent while the first one is still processing.
• Claims filed after the payer’s deadline.
• Payments posted incorrectly, which hides underpayments and denials.

Each of these is preventable with front-end checks, claim scrubbing and careful payment posting. When denials still happen, a structured denial management process fixes the claim and the root cause together.

How long the medical billing process takes

Timing depends on the payer, the contract and how clean the claim is. Medicare, for instance, does not pay a clean electronic claim until at least 14 days after it receives the claim. Commercial plans follow their contracts and state prompt-pay laws, which differ from state to state.

By contrast, a denied or rejected claim adds weeks, because it has to be corrected and processed again. That is why the steps before submission matter so much: they decide whether a claim pays on the first pass or enters a slower cycle of rework.

How to measure your billing process

A few numbers show how well the medical billing process works. Track them monthly and compare each month with your own baseline:

• Clean claim rate: the share of claims accepted on the first submission.
• Initial denial rate: the share of claims denied the first time the payer reviews them.
• Charge lag: the days between the date of service and charge entry.
• Days in AR: how long, on average, it takes to collect payment.
• Payment posting lag: the days between the deposit and posting. Our payment posting services keep this gap short.

When one number gets worse, trace it back to the step that owns it. For example, a jump in denials for eligibility points to step 2, while a rise in coding denials points to steps 4 and 6.

Frequently asked questions

What is a clearinghouse in medical billing?

A clearinghouse checks claims for format errors, converts them to the payer’s required electronic format, routes them to payers and returns acceptance, rejection and remittance reports.

What is the difference between a rejection and a denial?

A rejection happens before the payer processes the claim, usually because of a format or data error, so you fix it and resubmit. A denial happens after the payer processes the claim and decides not to pay, so you correct it or appeal.

What is the difference between CMS-1500 and UB-04?

The CMS-1500 (837P) is for professional services billed by physicians and clinics. The UB-04 (837I) is for institutional services billed by hospitals and other facilities.

Who is responsible for each step of medical billing?

The front desk owns registration, eligibility and copays; providers own documentation; coders own codes; and billers own claims, payment posting, denials and patient statements.

Can a practice outsource only part of the billing process?

Yes. Many practices keep the front desk in-house and outsource coding, claim submission, denial work and AR follow-up to a billing partner.