PHP and IOP billing: why substance use programs lose the days they delivered
A PHP or IOP day gets paid only when the claim proves the patient needed that level of care and the authorization was still alive when the day was delivered. Both live in the documentation, not the code.
That is what makes this billing unforgiving. PHP and IOP usually pay a per-diem, so one day is one claim for everything delivered that day. One missing note or a lapsed authorization voids the whole day, not a line of it. The level you bill also has to match what you ran that week: PHP means 20 or more structured hours, IOP roughly nine to nineteen. If the schedule and the notes do not carry the level, the day gets downgraded or recouped.
The bigger loss is quieter. Payers approve an admission, then re-review every week or two and can cut the authorization mid-stay. Miss that window, or send a thin continued-stay note, and those days become non-covered. Payers rarely authorize after the fact, so that loss is usually permanent, and almost all of it is preventable.
Clean billing here also means SUD-specific handling. These records fall under 42 CFR Part 2, stricter than HIPAA, so nothing goes to a payer without written consent on file. Every billed day traces to an individualized note that reconciles to attendance, the kind of claim that survives concurrent review and audit.
Altair is the done-for-you billing service, run by AI, backed by our expert in-house billers, for programs without a dedicated billing team. We keep the authorizations alive through concurrent review and bill clean enough to survive the audit.
Talk to us, and we will show you the days you are losing to lapsed authorizations.
Common questions
Do you handle prior authorizations and concurrent reviews?
Yes, and it is the core of what we do. We submit the initial authorization, track every continued-stay window, and prepare the medical-necessity justification each payer wants to keep the days approved. We never let an authorization lapse on a day you delivered, because payers rarely grant it back.
How do you handle 42 CFR Part 2 and SUD records?
SUD records are governed by 42 CFR Part 2, which is stricter than HIPAA. We work from written patient consent on file before anything goes to a payer, and we keep that release-of-information trail documented. A generic biller treating SUD like any other specialty is how programs get exposed.
We do not have a dedicated billing team. Is that a problem?
That is who this is built for. Altair is the done-for-you billing service, run by AI, backed by our expert in-house billers. The AI catches the documentation gaps and reconciles notes to attendance, and the billers defend the level of care through review and audit. You run the program, we run the billing.
Sources: ASAM levels of care and CMS PHP/IOP service-hour and per-diem requirements (2024-2026); 42 CFR Part 2 confidentiality (HHS OCR, 2024); payer utilization-review and continued-stay guidance; PHP/IOP documentation standards.