CDT 2026 is here: why un-updated software silently breaks claims

The ADA's CDT 2026 code set took effect on January 1, 2026. From that date, insurance payers validate claims against the new code set — which means any practice still filing CDT 2025 codes is not doing anything "wrong" in a clinical sense, but their claims start bouncing anyway.

Here is the part that deployment choices decide:

• Cloud platforms push the updated code set to every practice automatically. Nobody has to remember anything.
• On-premise installations typically receive code updates through version updates that someone at the practice (or their IT person) must actually apply. The software keeps running fine on the old codes — right up until the claims stop paying.

There is no error message that says "your code set is stale." The failure mode is silent: claims get rejected one by one, and the front desk assumes it is a payer problem.

• Ask your vendor in writing how CDT updates reach you: automatic, or a version you must install? This is a fair question regardless of deployment model — hybrid setups exist.
• If you are on-premise, confirm your update/subscription status. Many vendors deliver code updates only to practices with an active support plan. A lapsed support plan plus a January code change is the classic denial factory.
• Test one claim in early January and watch whether the payer accepts the new codes. Fifteen minutes of checking beats a month of rejections.
• Put it on the calendar every Q4 — this is not a one-time task. The code set changes annually by design.

We document whether each product's deployment model makes code updates automatic or manual in its product page (see the deployment dimension), because it is a real, recurring cost of self-hosting that sticker prices never mention. It is one of the "hidden costs of ownership" that our 3-year cost methodology is designed to surface.