Out-of-Network Reimbursement Rates: The Definitive Guide to Billing Insurance as a Behavioral Health Provider

If you've ever stared at a remittance advice wondering why your reimbursement came back at 40% of what you billed — or spent 45 minutes on hold with UnitedHealthcare only to get a vague answer about "usual and customary rates" — this guide is for you.

Out-of-network (OON) billing is one of the most misunderstood revenue streams in behavioral health. Done right, it lets you maintain clinical independence, work with a broader client base, and often get paid more than in-network rates allow. Done wrong, it becomes a documentation headache, a claims denial spiral, and a compliance risk.

This is the complete guide to understanding out-of-network reimbursement rates and how to bill insurance correctly as a therapist, LCSW, LPC, LMFT, or psychiatrist in 2026.

What "Out-of-Network" Actually Means for Mental Health Billing

When you're out-of-network (OON) with a payer, you have no contracted rate with that insurance company. Your client can still use their benefits — but you and the payer have no pre-negotiated fee schedule.

Here's what that means in practice:

You set your own fee. You bill at your full private-pay rate (your "billed charges").
The payer pays based on their internal benchmark — typically a percentage of the UCR (Usual, Customary, and Reasonable) rate or the Medicare fee schedule.
Your client pays the difference between what insurance reimburses and what you charge (called "balance billing").

For mental health services, OON benefits are governed by the Mental Health Parity and Addiction Equity Act (MHPAEA) — which means payers must apply OON mental health benefits at least as generously as they apply them to medical/surgical OON services. This is important leverage you should know.

How Payers Calculate Out-of-Network Reimbursement Rates

This is where it gets murky — and where most providers get shortchanged.

The Four Benchmarks Payers Use

| Benchmark | What It Means | Typical Payer | |---|---|---| | UCR (Usual, Customary & Reasonable) | Based on what providers in your zip code charge; sourced from databases like FAIR Health | Aetna, Cigna, some BCBS plans | | Medicare Fee Schedule % | A multiplier of Medicare's allowed amount (e.g., 110–150% of Medicare) | UnitedHealthcare, some Medicaid MCOs | | Billed Charges % | A flat percentage of whatever you bill (e.g., 60% of billed) | Older BCBS plans, some smaller carriers | | Negotiated Rate Equivalent | Matches or approximates in-network rates for that region | Some BCBS plans, post-No Surprises Act adjustments |

Pro tip: FAIR Health (fairhealthconsumer.org) lets you look up UCR rates by CPT code and zip code. Use this to set your billed charges strategically — you want your fee to be at or above the 80th percentile for your area so you're never leaving reimbursement on the table.

Typical OON Reimbursement Rates by Payer (2026 Estimates)

| Payer | OON Mental Health Reimbursement (Approx.) | Notes | |---|---|---| | UnitedHealthcare | 60–80% of UCR | Varies heavily by plan; OptumHealth manages behavioral health | | Aetna | 50–70% of UCR | Better rates in metro areas | | Cigna | 50–75% of billed charges or UCR | Some plans cap at Medicare +10% | | Anthem/BCBS | 70–90% of in-network equivalent | MHPAEA compliance generally strong | | Humana | 50–65% of UCR | Stricter medical necessity documentation required | | Oscar Health | 40–60% of UCR | More restrictive on OON benefits |

Important: These are estimates. Your actual reimbursement depends on the specific plan (HMO vs. PPO vs. EPO), your state, and the client's deductible status. Always verify benefits before the first session.

Step-by-Step: How to Bill Insurance as an Out-of-Network Provider

Step 1: Verify OON Benefits Before the First Session

Call the member services number on the back of the client's insurance card and ask these specific questions:

Does this plan include OON mental health benefits?
What is the OON deductible, and how much has been met?
What is the OON coinsurance percentage (e.g., 30% after deductible)?
Is a referral or prior authorization required for OON mental health services?
What is the plan's OON maximum out-of-pocket?
Does the plan use FAIR Health, Medicare rates, or billed charges as the UCR benchmark?

Document every call: Write down the date, time, rep name, and reference number. This protects you if benefits are later denied or misquoted.

Step 2: Create a Superbill (Not a Standard CMS-1500 — Yet)

As an OON provider, you typically don't submit claims directly. Instead, you give your client a superbill — a detailed receipt they submit to their insurance company for reimbursement.

A compliant superbill must include:

Your NPI number (Type 1 individual)
Your license type and number (LCSW, LPC, LMFT, MD/DO, etc.)
Your Tax ID or SSN
Practice name and address
Client's name, date of birth, and insurance member ID
Date(s) of service
CPT code(s) with full description
Diagnosis code(s) (ICD-10-CM) — primary first
Your billed charge per session
Modifier codes if applicable (e.g., Modifier 95 for telehealth)
Referring provider NPI (if required by the plan)
Place of service code (POS 11 = office, POS 02 = telehealth)

Missing even one of these fields is the #1 reason superbills get rejected. Period.

Step 3: Use the Right CPT Codes

Behavioral health has its own CPT code set. Using the wrong code — or an outdated one — triggers automatic denials.

Most Common Behavioral Health CPT Codes for OON Billing:

| CPT Code | Service | Typical Session Length | |---|---|---| | 90791 | Psychiatric diagnostic evaluation (initial intake) | 45–60 min | | 90792 | Psychiatric diagnostic evaluation with medical services (psychiatrists) | 45–60 min | | 90832 | Individual psychotherapy | 16–37 min | | 90834 | Individual psychotherapy | 38–52 min | | 90837 | Individual psychotherapy | 53+ min | | 90847 | Family psychotherapy with patient present | 50 min | | 90853 | Group psychotherapy | Variable | | 99213 / 99214 | E&M office visit (psychiatrists managing medication) | 20–39 / 40–54 min | | 96130 / 96131 | Psychological testing, evaluation | Per hour |

Telehealth modifier: Append Modifier 95 to any of the above when services are delivered via synchronous audio-video. Some payers still require GT modifier — verify per payer.

Step 4: Set Your Billed Charges Strategically

Your billed charge is not your private-pay rate. It's the amount you bill before insurance adjustments. Best practice: Set it 20–30% above your target reimbursement, anchored to the 80th percentile UCR for your zip code.

Example: If FAIR Health shows the 80th percentile for CPT 90837 in your zip code is $220, you might bill $240–$260. This ensures you capture the full UCR allowable from any payer that pays a percentage of billed charges.

Step 5: Direct Billing vs. Client-Reimbursement Model

You have two structural options as an OON provider:

Option A: Superbill Model (Client Submits)

You collect full fee from client at time of service
You provide a superbill; client submits it to their insurer
Client receives reimbursement directly
Pros: Simple, no claim filing, faster cash flow
Cons: Client must do the work; some won't follow through

Option B: Direct OON Claim Submission (You Submit)

You submit a CMS-1500 claim directly to the payer as an OON provider
Payment comes to you (with an assignment of benefits form signed by client)
Pros: You control the process; less client burden; assignment of benefits protects payment
Cons: More admin work; payers can still pay the client directly unless AOB is on file

For group practices billing more than 15–20 sessions/week OON, direct claim submission with assignment of benefits is almost always the better financial choice.

The No Surprises Act: What OON Providers Must Know in 2026

The No Surprises Act (NSA), fully in effect since 2022, significantly changed OON billing rules — particularly around Good Faith Estimates (GFEs).

What you must do:

Provide a Good Faith Estimate to any uninsured or self-pay client before the first session
For insured clients using OON benefits, a GFE may still be required depending on state law
The GFE must include your expected charges per session, anticipated number of sessions, and all applicable CPT/ICD-10 codes

What the NSA does NOT do:

It does not cap what you can charge OON clients
It does not require you to accept the payer's "benchmark" rate
It does not eliminate balance billing in the mental health context (unlike emergency medical care)

The Independent Dispute Resolution (IDR) process: If a payer reimburses you at a rate you believe is too low (for direct OON submissions), you can initiate the federal IDR process within 30 business days. The IDR arbitrator considers your billed charges, the qualifying payment amount, and market data. This is underutilized by behavioral health providers and worth knowing.

Common OON Billing Mistakes That Kill Your Reimbursement

Not verifying benefits before session one. If the client has an HMO or EPO plan, there are often zero OON benefits. Find out first.
Billing too low. If your billed charge is below the UCR benchmark, you'll receive less than you're entitled to.
Missing or incorrect ICD-10 codes. Every claim needs a valid, billable diagnosis. "Z00.00" (encounter for general examination) is not appropriate for therapy claims.
Forgetting the telehealth modifier. Payers flag and deny telehealth claims submitted with POS 02 but no Modifier 95 or GT.
No assignment of benefits on file. Without it, checks go to your client — and some clients don't forward them.
Submitting after timely filing limits. Most payers allow 90–180 days from date of service. Don't lose money to a calendar issue.
Incomplete superbills. A missing NPI, wrong date of birth, or absent license number will get the claim rejected at the clearinghouse level.

How Documentation Quality Directly Impacts OON Reimbursement

Here's what most billing guides won't tell you: your clinical notes are your billing defense.

When an OON claim is flagged for audit — and it happens more than you think — payers request your progress notes to confirm:

Medical necessity of the service
Level of care billed (e.g., 90837 requires 53+ minutes of face-to-face psychotherapy)
Consistency between diagnosis and treatment modality
Documentation of session content, interventions, and clinical response

If your notes don't support the CPT code billed, you face recoupment demands. Insurers like UnitedHealth/Optum, Cigna, and Aetna have entire teams whose job it is to audit OON behavioral health claims.

This is exactly why platforms like Mozu Health exist. Mozu's AI-powered documentation engine is built specifically for behavioral health — it helps you generate HIPAA-compliant progress notes that are not just clinically sound, but billing-code-consistent and audit-defensible. Every note Mozu generates is aligned to the CPT code billed, the documented session length, and the ICD-10 diagnosis — so you're covered if a payer comes knocking.

Frequently Asked Questions: OON Billing for Therapists and Psychiatrists

1. Can I bill insurance if I'm not credentialed with them?

Yes — that's the definition of OON billing. You don't need to be credentialed or paneled to submit OON claims or provide superbills. However, some plans (HMO, EPO) have no OON benefits at all, so clients with those plans would be fully self-pay.

2. What's the difference between a superbill and a CMS-1500?

A superbill is a detailed receipt you give to your client to submit to insurance. A CMS-1500 is the standardized paper (or electronic 837P) claim form used for direct provider-to-payer billing. Both use the same CPT and ICD-10 codes, but the CMS-1500 is more formal, requires a clearinghouse or direct payer submission, and enables direct payment to you.

3. How do I know if my billed charges are set correctly?

Use FAIR Health (fairhealthconsumer.org) to look up your CPT codes by zip code. Aim for the 80th percentile or higher. Review your rates annually — UCR benchmarks shift with regional market data.

4. Can payers audit my OON claims even if I'm not contracted?

Absolutely. Payers can — and do — audit OON claims, especially for high-volume providers. If they find documentation doesn't support the level of service billed, they can demand recoupment and, in egregious cases, refer for fraud investigation. Solid clinical notes are your primary defense.

5. What if a client's insurance denies the OON claim?

First, request the denial reason in writing (EOB). Common reasons include: non-covered service, lack of prior authorization, timely filing exceeded, or insufficient medical necessity documentation. You can appeal — and for mental health parity violations, you have strong grounds. Provide a peer-reviewed appeal letter with clinical rationale and cite MHPAEA if the denial would not have been applied to an equivalent medical service.

6. Is telehealth reimbursed at the same OON rate as in-person?

It depends on the plan. Post-COVID, most major payers (UnitedHealthcare, Aetna, Cigna, Anthem) have maintained telehealth parity for behavioral health at OON rates. Always verify with the specific plan, and always append Modifier 95 (or GT where required).

7. Do I need a referral to bill OON for mental health?

For most PPO plans, no. For HMO/EPO or plans with managed behavioral health carve-outs (like Optum or Magellan), you may need prior authorization even for OON benefits. Ask specifically during your benefits verification call.

Final Thoughts: OON Billing Done Right Is a Competitive Advantage

Out-of-network billing isn't a workaround — it's a legitimate, strategically smart model for many behavioral health providers. It gives you fee-setting freedom, eliminates the administrative burden of credentialing negotiations, and often results in higher net reimbursement per session than in-network contracts allow.

But it only works when your billing is accurate, your documentation is airtight, and your processes are consistent. One missed modifier, one vague progress note, one overlooked authorization requirement — and you're either leaving money on the table or inviting an audit.

That's the gap Mozu Health was built to close.

Try Mozu Health: Documentation That Protects Your Revenue

Mozu Health is the AI-powered clinical documentation platform built exclusively for behavioral health providers — therapists, LPCs, LCSWs, LMFTs, and psychiatrists who want to spend less time on paperwork and more time with clients.

With Mozu, you get:

✅ AI-generated progress notes aligned to your CPT codes and ICD-10 diagnoses
✅ Audit-defensible documentation that supports the level of care you bill
✅ HIPAA-compliant infrastructure — no compromises
✅ Superbill and billing support built into your workflow
✅ Time-of-service documentation so notes are never piling up at 11pm

Whether you're fully OON, hybrid, or building toward private pay, your clinical notes are the foundation of your revenue. Don't leave them to chance.

👉 Try Mozu Health free at mozuhealth.com — and see how much easier compliant, billable documentation can be.

Disclaimer: This article is for educational purposes only and does not constitute legal, billing, or compliance advice. Reimbursement rates and payer policies change frequently. Consult a certified medical billing specialist or healthcare attorney for guidance specific to your practice.

Out-of-Network Reimbursement Rates: How to Bill Insurance in 2026