Every practice writes off some charges. However, not every write-off is the same, and some should never happen at all. In this guide, you will learn what a write off in medical billing is, the main types, and how to post each one the right way.
Understanding Medical Billing Write‑Offs
What Are Write‑Offs?
A write off in medical billing is an amount you remove from a patient’s account and will not collect. In other words, it lowers the balance without a payment. For example, if you bill $200 and the payer’s contract allows $140, you write off the $60 difference.
How Write‑Offs Work
First, the payer sends an ERA or EOB. Then, your billing team posts the payment and any adjustments. Finally, the remaining balance either goes to the patient or gets written off.
Types of Write Off in Medical Billing
Contractual Write‑Offs
Contractual write-offs come from your payer contracts. Specifically, they cover the gap between your charge and the allowed amount. Because you agreed to these rates, you cannot bill the patient for this amount. To learn more, read our guide on contractual allowance adjustments.
Bad Debt Write‑Offs
Bad debt applies when a patient does not pay after you make reasonable collection efforts. For instance, you may send several statements and make calls first. After that, you may write off the balance or send it to collections.
Charity Care Write‑Offs
Charity care helps patients who cannot afford their bills. Usually, the practice follows a written financial assistance policy. So, apply it the same way for every patient who qualifies.
Insurance Write‑Offs in Medical Billing
Common Insurance Adjustment Scenarios
| Code | Meaning | Action |
| CO-45 | Charge exceeds the fee schedule | Contractual write-off |
| CO-97 | Service is bundled into another | Review, then write off if correct |
| CO-29 | Timely filing limit expired | Write off; you cannot bill the patient |
| PR-1 | Deductible | Bill the patient |
| PR-2 | Coinsurance | Bill the patient |
As a rule, “CO” means the provider owns the amount, while “PR” means the patient owes it. For the full list, see the X12 claim adjustment reason codes. You can also read about the CO-29 denial code in detail.
Impact on the Revenue Cycle and Reporting
Write-offs affect your net collection rate and A/R. For example, a rise in timely filing write-offs signals a process problem. Therefore, track each type on its own, not as one total. In addition, review avoidable write-offs with your claim management team.
How to Post a Write Off in Medical Billing
Step 1: Match Claim Response
First, match the ERA or EOB to the right claim and line. Also, confirm the patient, date of service, and codes.
Step 2: Apply Adjustment Codes
Next, enter the adjustment with the correct reason code. For instance, use the CARC from the remittance, such as CO-45. Learn the difference between code types in our RARC vs CARC guide.
Step 3: Document Physician Notes or Denials
Then, add a short note that explains the write-off. Above all, never write off a denial before you check whether you can appeal it. Sometimes, a fix to the billing codes can recover the payment.
Step 4: Update Patient Balance
After that, move any patient responsibility, such as deductibles, to the patient’s account. Meanwhile, keep contractual amounts off the patient bill.
Step 5: Reconcile and Review Regularly
Finally, reconcile your write-offs each month. For example, compare totals by type and payer. As a result, your financial reporting stays accurate.
Conclusion
To sum up, a write off in medical billing is not always lost money. Contractual write-offs are normal. On the other hand, timely filing and denial write-offs often point to fixable problems. So, post each one with the right code, track them by type, and act on the trends.
FAQs
What is a write-off in medical billing?
It is an amount removed from a patient account that the practice will not collect.
Can I bill the patient for a contractual write-off?
No. Instead, your payer contract requires you to absorb that amount.
What is the difference between a write-off and an adjustment?
An adjustment is any change to a balance. A write-off, by contrast, is an adjustment you do not expect to collect.
Is bad debt the same as charity care?
No. Bad debt comes from unpaid bills, whereas charity care follows a policy for patients in need.
