Can You Bill ABA Therapy After an Authorization Expires? Rules, Denials and Reauthorization

No. You cannot bill ABA therapy for dates of service outside an active authorization window and payers deny those claims under reason code 197 or 15. The sessions happened. The notes are clean. The units are logged. But if the authorization ended March 31 and the child was seen April 2, the payer reads it as though no approval ever existed. Authorization problems drive about 34% of all ABA claim denials and expired dates are the most common trigger in that bucket.

Can you bill ABA therapy after authorization expires?

You can submit the claim. You usually won't get paid for it.

Payers treat the authorization window as a hard calendar boundary. A three-month approval running January 1 to March 31 covers sessions through March 31 and nothing after. A pending reauthorization does not extend the old one either, which is where most clinics get caught. Your BCBA sent the renewal on time, the payer is still reviewing it, therapy continued because stopping mid-program is clinically wrong and every session in that gap bills against nothing.

Two narrow paths exist: a retroactive authorization request, or a backdated approval covering the gap dates. Neither is guaranteed and both are payer-specific.

What happens to ABA claims with an expired authorization?

The claim denies and the balance becomes your write-off risk. You cannot bill the family for it. A CO-prefixed denial is provider responsibility, so passing that cost to parents is a compliance problem, not a workaround.

Reason code	What the payer means	What it usually is in ABA	Next step
197	Authorization absent	Session date fell after the auth end date	Retro auth request, or appeal
15	Auth number invalid or doesn't apply	Old auth number keyed onto a new period	Correct and resubmit
198	Authorization exceeded	Units burned before the end date	Request added units or an extension

Learn the difference. A 15 is a five-minute fix. A 197 can take 60 days. Our breakdown of ABA claim denials covers the wider denial mix.

Check these ABA authorization details before you rebill

Most expired-auth denials are not actually expired. They're mismatched. Pull the letter and the claim side by side.

• End date on the letter, not the date in your software. They drift.

• Units remaining. A 198 means you ran out of units, not time.

• CPT codes on the approval. Some payers authorize 97153 and 97155 separately. Check yours against the ABA therapy billing CPT codes list.

• Rendering provider. A covering supervisor's NPI breaks the match.

• Place of service. Clinic-approved auths deny for in-home dates in Texas and Florida Medicaid plans.
  

How do you fix expired ABA billing claims?

Work the gap dates fastest path first. Call the payer and ask directly whether retro authorization is available for those dates and whether a pending renewal can be backdated. Many plans allow it inside 30 to 90 days of service and most billers never ask.

If retro auth is off the table, appeal with session notes, the treatment plan, dated proof your renewal went out before expiration and a short medical necessity narrative. First-level appeals usually run 30 to 60 days from the denial notice.

Timely filing runs the whole time, 90 to 365 days by payer. A claim you're still fighting at day 300 can die on the filing clock. Clinics in New Jersey, California and Dubai all hit the same wall. Prior authorization services handle retro requests and appeal packets so your BCBAs aren't stuck on payer phone trees.

ABA reauthorization timeline and documentation payers review

Start the renewal 30 days out, or when 75% of units are used, whichever comes first.

Commercial payers cut standard ABA windows from six months to three during 2025 and those windows held into 2026. Approval turnaround is 7 to 14 business days for most commercial plans and 5 to 30-plus days for state Medicaid MCOs. A packet sent two weeks out is already late for some plans.

Reviewers look for an updated treatment plan with measurable dated progress, the specific interventions used rather than templated summaries, caregiver training goals and hours justified against graphed data. Vague notes are a rejection trigger on their own now. Full payer requirements sit in our ABA billing guidelines.

How to prevent ABA authorization gaps and billing denials

Prevention is cheaper than appeals and it's a tracking problem, not a clinical one.

Log the expiration date and unit balance the day approval arrives. Set alerts at 30 days and 14 days. Check unit balances daily, because a fast-scaling client can burn a month of units in ten. Then add the control most clinics skip: a claim hold that stops any date of service outside the active window from going out. A held claim you fix in 48 hours costs nothing. A denied one costs 60 days. An experienced ABA billing company catches these before they show up in aging.

How ABA therapy billing services manage authorizations

The work here is boring on purpose. Watch every expiration date across every payer. Submit renewals on a schedule matched to each plan's real review time. Escalate anything still pending 10 days out. Hold claims that fall outside the window instead of letting them deny.

That discipline is the gap between a 5% authorization denial rate and a 12% one. ABA therapy billing services that own authorization tracking, scrubbing and denial follow-up as one workflow catch the problem while it's still fixable.

Frequently asked questions

Can you bill the parent if the ABA authorization expired? 

No. Authorization denials returned with a CO prefix are contractual provider responsibility, so the balance cannot be transferred to the family. Billing parents for an expired-auth denial adds compliance exposure on top of lost revenue.

Will a payer approve retroactive authorization for ABA therapy? 

Sometimes. Retro auth is payer-specific and never guaranteed. The request needs clinical documentation, the reason authorization wasn't in place beforehand and submission inside the payer's stated window. Ask before writing the dates off.

Does a pending reauthorization cover ABA sessions after the old one expires?

No. A submitted request is not an approved one. Sessions between the old expiration and the new approval bill against no active authorization and deny at 197. Send renewal packets 2 to 4 weeks early.

What to take from this

Expired authorization denials are a calendar failure, not a clinical one. The claim is correct and still doesn't pay. Fix the ones you have by checking for a mismatch first, asking about retro auth second, appealing third, always inside timely filing. Then close the door behind you with alerts at 30 and 14 days, daily unit tracking and a claim hold on any date outside the window.