Most workers’-comp denials are predictable. By the time a request for authorization (RFA) comes back rejected, the reason was usually visible in the paperwork before it ever left your office — a body part that isn’t on the accepted claim, a request that outruns the treatment guideline, a report missing the objective finding that would have justified it. Utilization review isn’t reading for nuance. It’s checking the request against a short, knowable list of rules, and increasingly it’s doing that check with software. This post walks the 12 reasons treating providers get RFAs denied, in roughly the order you’ll hit them, and what to verify at the point of request so a denial doesn’t cost you a month and an appeal.
One framing point first. Plaintiff-side and industry coverage through 2026 reports that a growing share of workers’-comp payers — by some accounts roughly 40% — now use automated systems to flag and deny requests, with ortho and pain clinics taking the sharpest edge of automated cost-containment denial. Treat that as a reason to be mechanical, not discouraged: an automated reviewer denies on the same predictable patterns every time, which means a provider who checks for those patterns before submitting can beat most of them on the first pass.
The 12 predictable denial reasons
1. The request is for a body part that isn’t accepted on the claim. This is the single most common technical denial and the easiest to miss. If the claim accepts a lumbar injury and you request an MRI of the cervical spine, it’s denied on contact — not on medical merit. Confirm the accepted body parts before every request.
2. It exceeds the treatment guideline. Most states adjudicate medical necessity against an evidence-based standard — MTUS in California, ODG or ACOEM elsewhere. A request that runs past what the guideline supports (imaging too early, a procedure before the guideline’s conservative threshold) gets denied even when the patient clearly needs it. Know which guideline your state applies and where your request sits against it.
3. There’s no documented failed conservative care. Guidelines gate the expensive stuff behind documented, failed conservative treatment. Request surgery or advanced imaging without a record of PT, medication, or activity modification that didn’t work, and UR denies for lack of a completed conservative trial — even if you and the patient both know it’s futile.
4. The medical necessity documentation is thin. The request has to be supported by the report attached to it. If the RFA asks for a service the accompanying PR-2 / progress note never justifies — no exam findings, no objective basis, no rationale tying the request to the injury — it reads as unsupported and gets denied.
5. No functional deficit or work status is documented. WC is about function. Denials and appeals both turn on how the injury limits activities of daily living and the ability to work. A request that doesn’t document the functional deficit it’s meant to fix hands the reviewer an easy denial and, later, a weaker appeal.
6. The coding doesn’t match the documented diagnosis. An ICD-10 that doesn’t map to the accepted condition, or a CPT that doesn’t match what the note describes, triggers a coding-mismatch denial that has nothing to do with whether the care is needed. Verify the codes against the documented diagnosis and the accepted claim, not habit.
7. The RFA form itself is incomplete. Missing fields, missing signature, missing required supporting report — administrative denials that never reach the clinical question. A request that’s technically defective is dead on arrival regardless of merit.
8. It’s late. Every state runs RFA and appeal timelines. Submit outside the window and the denial is procedural. The clock is knowable in advance; missing it is an operational failure, not a clinical one.
9. It exceeds a hard visit or dollar cap. Some jurisdictions cap therapy visits (California’s 24-visit PT cap is the classic example) or set utilization thresholds. Requesting past a cap without the documentation that justifies an exception gets the overage denied automatically.
10. It duplicates something already authorized or provided. Overlapping or duplicate requests — the same service authorized under a prior RFA, or already delivered — get denied as redundant. This happens most when authorizations aren’t tracked in one place and staff can’t see what’s already open.
11. The underlying claim isn’t accepted yet. If liability is still in dispute or the claim is delayed, there’s no accepted condition to authorize against, and requests sit in denial or limbo until the claim itself resolves. Know the claim’s status before you spend effort on the RFA.
12. There’s no documented treatment response. Requesting continuation of a modality with no charted improvement — and no plan to change course — reads as care that isn’t working. Document the response to prior treatment and the clinical reasoning for continuing, or expect a “no demonstrated functional benefit” denial.
The pattern under all twelve
Notice what almost none of these are: a genuine clinical dispute about whether the patient needs care. The overwhelming majority are verification failures — a body part, a code, a guideline threshold, a missing report, a blown deadline. Each one is knowable at the moment you build the request. That’s what “denial prediction” actually means for a treating provider: not a crystal ball, but a checklist run against the claim file and the guideline before the RFA goes out, so the fixable reasons get fixed while they’re still cheap to fix.
State rules vary, and this list is a starting framework, not legal or coding advice for your jurisdiction — California’s UR/IMR machinery is far more formalized than many states’ (see our guide to California’s April 2026 UR/IMR overhaul for the current deadlines), and caps, forms, and timelines differ everywhere. Confirm the specifics for the states you bill.
If you’re also fighting prior-auth denials on the group-health side, the same “prove-it-before-you-submit” discipline applies there; see our breakdown of gold-carding and prior-auth approval-rate tracking. And because automated cost-containment denial hits ortho and pain practices hardest, the operational stakes are highest for those clinics — more on that on the pain management and orthopedics pages.
Where an agent helps
Denial prediction is a documentation-and-verification problem that repeats on every request, which is exactly the kind of always-on, detail-checking work an agent is built for. Kaira’s workers’-comp automation is designed to flag denial risk before a request goes out — checking the request against the accepted body parts, surfacing coding mismatches, and drafting the auth letter, appeal, and peer-to-peer or letter-of-medical- necessity language when a denial does land — with your staff reviewing and approving everything before it’s filed. It tracks each authorization through its lifecycle so duplicate requests and blown deadlines don’t slip, and it keeps the request tied to the documentation that supports it.
The boundary matters: an agent surfaces risk and drafts language; it doesn’t practice medicine, decide medical necessity, or file anything on its own. What it removes is the predictable half of the denial problem — the body part that wasn’t checked, the code that didn’t match, the report that never got attached — so your clinical judgment isn’t losing to a paperwork miss. For the wider operational picture, see the Kaira platform overview; if you run a lien- and WC-heavy practice, the Texas personal-injury practice guide puts authorization work in the context of the whole operation.
A denied RFA costs weeks the patient spends waiting and hours your staff spends appealing. Most of those denials were avoidable at the point of request. The practices that treat the denial list as a pre-submission checklist — not a post-denial surprise — are the ones whose patients keep moving through care.