Why is our AR over 90 days climbing?

Start with three numbers

The trend matters more than the number. A practice whose AR over 90 has been flat for two years has a process that needs improving. A practice whose figure has climbed for two quarters has something specific that broke, and this page is about finding it.

What should AR over 90 days actually be?

Under 15 percent of total AR is the common working target, and HFMA sets a stricter bar at under 10 percent. Above 20 percent indicates something systemic. But benchmarks are less useful here than most articles suggest, because payer mix moves them more than performance does. A practice with heavy Medicaid or workers compensation carries structurally longer AR than a commercial practice doing everything wrong.

A correction worth knowing

You will see a figure of roughly 13.5 percent quoted as the MGMA benchmark for AR over 90 days across a lot of billing company content. It is a real number in the wrong place. It comes from MGMA's 2021 DataDive figure for AR over 120 days in multispecialty practices, which is a different bucket, a different cohort, and five years old.

We mention it because if you have been comparing yourself against it, you have been comparing against the wrong thing.

What to actually compare against

Three comparisons, in order of usefulness:

1. 1.Your own trend, month over month. The most informative number you have.

2. 2.Your specialty cohort. Surgical specialties carry more bundling denials. Behavioural health carries more medical necessity denials. A blended benchmark tells you little.

3. 3.Your own payer-by-payer breakdown. Two practices both averaging 35 days in AR can have completely different aging profiles. A single blended figure hides a concentrated problem.

Free tool

AR aging benchmark comparator

Enter your aging buckets and see where you sit against published benchmarks, plus a ranked list of what is most likely causing it. Runs in your browser, sends nothing anywhere, and needs no patient information.

Given your numbers, what is actually causing it?

The main causes of AR aging leave different fingerprints. The mistake most practices make is treating a rising over-90 bucket as a follow-up problem and putting more people on the phone. Sometimes that is right. Often the claim never reached the payer, or was denied for something the front desk could have caught, or is one payer behaving differently from the rest. Find the fingerprint first.

What to do first

Re-sort your worklist before you do anything else. Most practices work aged AR by largest balance first, which feels right and costs money. Work by deadline proximity instead. A small claim a week from its filing deadline is worth more than a large claim with six months left, because one becomes zero and the other does not.

This week, and free

1. 1. Re-sort the aged worklist by deadline, then by recoverability. Correctable-error denials first, then claims near their filing deadline, then high value recoverable, then formal appeals. Stop working genuinely dead claims entirely.
2. 2. Pull the clearinghouse rejection queue. Every rejection nobody retrieved is a claim that never reached a payer and never appeared in your aging report.
3. 3. Run a payer-by-payer days in AR breakdown. Ten minutes, and it either isolates the problem to one payer or rules that out.
4. 4. Separate patient AR from insurance AR. Different problem, different workflow, and averaging them hides both.
5. 5. Reconcile unposted remittances and confirm your ERA and EFT enrolments are intact. Particularly if you changed clearinghouse after 2024.

Over the next few weeks

6. 6. Build a follow-up cadence with a worklist and logged touch history. Work denials within 14 days of receipt, before they migrate into the 90-plus bucket.
7. 7. Run the submitted-versus-paid variance report to detect downcoding.
8. 8. Verify credentialing and enrolment for every provider, and hold new provider claims until enrolment is effective rather than billing and being denied.
9. 9. Fix eligibility verification at every visit, and capture prior authorisation before service for the procedures that need it.
10. 10. Push the clean claim rate toward 95 percent. Every claim that fails on first pass adds roughly two to four weeks to its effective cycle.

Structural, over months

11. 11. Close the loop from denials back to the front desk and coding, so a back-end denial becomes a front-end fix rather than a recurring cost.
12. 12. Collect at time of service and offer payment plans, because the patient share of revenue is growing whether or not you adapt to it.
13. 13. If your team cannot clear the backlog and keep current work current at the same time, separate the two. Backlog cleanup that competes with daily follow-up usually loses, and then you have two problems.

Free tool

Timely filing triage

Enter a payer and a date of service to see how long you have, and how that claim should rank against the others on your worklist.

Which old claims are dead, and which are just aged?

Age does not determine recoverability. The filing window does. A 135 day old Medicare claim is comfortably alive, because Medicare allows 365 days from date of service under 42 CFR 424.44. A 100 day old claim on a 90 day commercial contract is dead, and no amount of follow-up will change that. Practices routinely spend labour on the second category while the first quietly expires.

Appeal windows are separate and shorter, and they run from the remittance date rather than the date of service. Corrected claims often must be filed within 60 days of the original denial, and the original filing clock does not reset.

Sort your aged AR into these two piles before you assign anyone to work it. The labour you free up by abandoning genuinely dead claims is usually enough to properly work the live ones.

What changed between 2024 and 2026

If your AR over 90 has worsened and you cannot find an internal cause, the environment is a real part of the answer. Denial rates rose, the type of denial shifted toward the kinds that are harder to overturn, tens of millions of people lost Medicaid coverage, and patient deductibles kept climbing. None of this excuses a broken process, but it does mean a well-run practice can be losing ground while doing nothing differently.

Denials rose, and got harder

Kodiak Solutions, drawing on data from more than 2,100 hospitals and 300,000 physicians, reported that the initial denial rate rose to 11.81 percent of claims in 2024, up from 11.5 percent in 2023 and 10.2 percent in 2020. True days in AR rose 5.2 percent year on year.

The composition matters more than the total. Authorisation related denials fell, while medical necessity denials rose around 5 percent and requests for information rose around 5.4 percent. Those are the categories that take longest to resolve.

Kodiak's own reading, from its vice president of revenue cycle intelligence, is that payers appear to be using initial denials to slow payment even though roughly 90 percent of claims are ultimately paid.

Automated downcoding arrived

Cigna introduced reimbursement policy R49 on 1 October 2025, automatically downcoding certain office and consultation codes by one level where its records indicated a provider coded above peers. Physician groups including the American Medical Association opposed it, the California Department of Managed Health Care reviewed it, and Cigna paused the policy around 8 October 2025.

Several Blue Cross Blue Shield licensees apply downcoding to level 4 and 5 office visits. Anthem reversed a proposed anaesthesia time policy in December 2024 after opposition led by the American Society of Anesthesiologists.

The pattern is consistent: automated adjustment introduced, opposed, sometimes paused. What it means practically is that a submitted-versus-paid variance check now belongs in your monthly routine.

Medicaid coverage churned

The Medicaid continuous enrolment unwinding began on 1 April 2023. As of September 2024, KFF's tracker recorded at least 25.2 million people disenrolled. Around 69 percent of those disenrollments were for procedural reasons, meaning paperwork, rather than confirmed ineligibility. Total enrolment fell from roughly 94 million in March 2023 to about 80 million by September 2024.

The 2025 reconciliation law adds federal Medicaid work requirements, with states implementing from January 2027 and several moving earlier.

For a practice, this means patients presenting as insured who turn out to be retroactively ineligible, which converts expected insurance revenue into patient bad debt without warning.

Patient balances grew

KFF's 2025 Employer Health Benefits Survey put the average single coverage deductible at $1,886, up 17 percent over five years. At firms with 10 to 199 workers the average is $2,631, and 36 percent of covered workers at those firms face a deductible of at least $3,000.

Kodiak reported that providers collected 34.46 percent of what insured patients owed in 2024, down from 37.58 percent the year before.

More of your revenue is in the slowest, hardest bucket, and less of it is being collected.

The Change Healthcare outage

The ransomware attack on Change Healthcare on 21 February 2024 halted claims submission, eligibility verification and remittance across a clearinghouse handling roughly a third of US patient records. Nearly 94 percent of hospitals reported financial repercussions.

The lasting effect for independent practices is quieter. Practices that migrated to another clearinghouse in 2024 often carry residual mapping and enrolment gaps: wrong payer IDs, incomplete ERA re-enrolment, whole payers silently failing to submit. If your AR started worsening in 2024 and never recovered, check this before anything else.

Is it our billing company?

Possibly, and it is worth ruling in or out properly rather than guessing. The test is not your numbers, it is what your billing company can produce when you ask. A company managing your revenue cycle can give you an AR aging split by payer and provider, a denial breakdown by reason code, and an appeal overturn rate, on request and the same day.

We have written that diagnosis separately, including the six reports to ask for and what evasion looks like on each.

Common questions

Sources

• ●42 CFR 424.44, Medicare timely filing
• ●CMS, Interoperability and Prior Authorization Final Rule CMS-0057-F
• ●KFF, Medicaid enrolment and unwinding tracker
• ●KFF, Employer Health Benefits Survey 2025
• ●MGMA, Cost and Revenue Survey 2024
• ●HFMA MAP Keys
• ●Kodiak Solutions revenue cycle data, 2024 and 2025
• ●Cigna, reimbursement policy R49