Dental timely filing limits: the deadline that turns paid claims into write-offs

The short answer. Timely filing is the maximum time a practice has to submit a claim after the date of service. Most payers set it somewhere between 90 and 180 days, and some as short as three months. Miss it and the claim is denied purely on the deadline, no matter how valid the treatment. Worse, when the practice is at fault the balance often cannot be passed to the patient, so a payable claim becomes a write-off. The good news: these are almost entirely preventable, and even a timely filing denial can usually be appealed with proof of submission.

Every payer sets a clock that starts on the date of service. Submit the claim before it runs out and the claim is considered on its merits. Submit after, and it is denied for timely filing regardless of the clinical facts. The windows vary:

• Most commercial payers fall somewhere between 90 and 180 days from the date of service.
• Some plans run as tight as a three-month window, which goes by faster than it sounds once a claim sits.
• Medicaid and certain plans can be stricter still, with their own deadlines that need tracking separately.

Because the limit is different for every carrier, there is no single safe number. The practical rule is to treat every claim as time-sensitive and to know each payer's window, rather than assume there is room to spare.

A timely filing denial is not just a delayed payment, it is often a permanent loss. When the practice missed the deadline, most contracts prevent balance-billing the patient for it, since the patient did nothing wrong. So the amount is not deferred, it is gone, and it lands as a write-off that quietly drags down the collection rate.

That is what makes timely filing different from a clinical denial you can rework. The claim was payable. The only thing that killed it was the calendar. This is why aging claims have to be worked before they cross each payer's limit, not after, and it ties directly into keeping AR from aging past 90 days, where the timely filing risk climbs fast.

The window almost always starts on the date of service, but a few situations change how it is counted, and knowing them is what saves claims that look late but are not:

• Secondary claims are often counted from the date the primary plan paid, not the original date of service, since you cannot bill the secondary until the primary explanation of benefits is in hand. Coordination-of-benefits delays are a legitimate reason a secondary claim arrives later.
• Corrected and resubmitted claims can have their own rules. Some payers count a corrected claim against the original filing date if the first one was timely, while others restart the clock, so it is worth confirming rather than assuming.
• Retroactive eligibility, where a patient's coverage is added or changed after the visit, can reset or extend the window, because the practice could not have billed a plan it did not yet know about.
• Payer or clearinghouse errors, such as a claim the system shows as sent but the carrier never received, are grounds to have the deadline excused when you have the submission record to prove it.

The throughline: a claim that looks past the deadline is not always lost. If one of these situations applies and you have the documentation, the payer is often required to consider it. That is where a clean submission trail turns a write-off back into a payment.

Do not treat a timely filing denial as automatically final. Even when a contract says claims will not be paid past three months, six months, or a year, the denial can usually be appealed if you can show the claim was actually handled on time. It is one of the more winnable appeals when the documentation exists.

The appeal itself is a written request to reconsider, a phone call does not count, and the strongest evidence is proof of timely submission, typically a clearinghouse report showing the original date the claim was sent. Pair that with a clear letter explaining why the claim should be reconsidered. Watch the appeal deadline too: plans often allow as little as 90 days from the denial to appeal, and missing that closes the door for good. The full appeal mechanics are covered in dental insurance appeals.

This is one of the most preventable denial categories, because it is a workflow problem, not a clinical one:

• Submit daily, not in batches that sit for weeks. Every day a claim waits is a day off the clock.
• Work the aging report before claims approach any payer's deadline, not after they cross it.
• Track filing limits by carrier, since they differ and the tightest ones bite first.
• Keep submission records, so if a claim is ever questioned you can prove when it went out.
• Follow up early on unpaid claims instead of assuming no news means it is processing.

Most timely filing losses come from claims that were simply left too long. Consistent daily submission and disciplined follow-up prevent the large majority of them. If you suspect claims are aging out and becoming write-offs, a free AR analysis shows exactly how much is at risk and how old your aging really is.