Out-of-Network Reimbursement Letter Template for Therapy

What Is Out-of-Network Reimbursement?

Out-of-network reimbursement is the process by which a client receives partial payment from their insurance company for therapy services provided by a clinician who is not contracted with their insurance plan. When a therapist is out-of-network, there is no direct billing relationship with the insurer. Instead, the client typically pays the therapist's full fee at the time of service and then submits a claim to their insurance company to recover a portion of the cost.

The amount reimbursed depends on the client's specific plan benefits, including their out-of-network deductible, coinsurance percentage, and the insurer's allowed amount for the service. Most PPO and POS plans include out-of-network benefits, while HMO and many EPO plans do not cover out-of-network services at all.

As a therapist, you can significantly help your clients navigate this process by providing accurate superbills, verifying their benefits, and in some cases submitting claims on their behalf. Proper documentation is the single most important factor in ensuring timely and accurate reimbursement.

When You Need It

Out-of-network reimbursement documentation is relevant in these situations:

• You are a private pay practice. You do not participate in any insurance panels but want to help clients use their out-of-network benefits to offset treatment costs.
• Client has out-of-network benefits. The client's plan covers out-of-network providers at a reduced rate and the client wants to access those benefits.
• Client cannot find an in-network provider. In-network options are unavailable or have excessive wait times, and a single case agreement was denied or not pursued.
• Client is transitioning plans. A client who was previously in-network with you changes to a plan where you are out-of-network and wishes to continue treatment.
• Client requests a superbill. Any client who pays out of pocket and asks for documentation to submit to their insurance needs a properly formatted superbill and may benefit from a reimbursement support letter.

Key Components

Successful out-of-network reimbursement requires the following documentation elements:

1. Superbill. A detailed receipt that includes all the information an insurer needs to process a claim: provider NPI, tax ID, license information, client demographics, dates of service, CPT codes, ICD-10 diagnosis codes, fees charged, and amount paid.
2. CMS-1500 claim form. The standardized claim form used to submit professional services to insurance. This can be submitted by either the client or the provider.
3. Client benefit verification. Written confirmation of the client's out-of-network benefits, including the deductible amount, deductible met to date, coinsurance percentage, and any session limits.
4. Reimbursement request letter. A cover letter submitted with the claim that provides clinical context and supports the medical necessity of treatment.
5. Assignment of benefits form (optional). If you are submitting claims on the client's behalf and want payment sent to your practice, the client must sign an assignment of benefits authorizing the insurer to pay you directly.

How to Write It Step by Step

Step 1: Verify the client's out-of-network benefits. Before the first session, call the insurance company using the number on the back of the client's insurance card. Ask specifically about behavioral health out-of-network benefits. Record the out-of-network deductible (individual and family), how much of the deductible has been met, the coinsurance percentage (how much the plan pays after the deductible), the out-of-network out-of-pocket maximum, any session limits for outpatient mental health, the allowed amount or usual and customary rate for CPT codes 90834 and 90837 in your zip code, and the correct claims mailing address or electronic submission process. Document the date, representative name, and reference number for this call.

Step 2: Provide the client with a superbill. After each session or on a monthly basis, generate a superbill that includes your full practice name and address, your NPI and tax ID numbers, your license type and number, the client's full name, date of birth, and address, the client's insurance member ID and group number, the date of service, the place of service code (11 for office, 10 for telehealth), the CPT code with exact session duration, the ICD-10 diagnosis code or codes, your fee for the service, and the amount the client paid. Ensure the diagnosis code on the superbill matches the diagnosis documented in the clinical record.

Step 3: Complete the CMS-1500 form. If you are submitting claims on behalf of the client, complete a CMS-1500 form. Key fields include Box 1 (type of insurance), Box 2 (patient name), Box 21 (diagnosis codes), Box 24 (service lines with dates, CPT codes, and charges), and Box 33 (billing provider information). Many EHR systems generate CMS-1500 forms automatically from superbill data.

Step 4: Write the reimbursement request letter. Draft a cover letter that identifies the client by name, date of birth, and member ID, states that you verified out-of-network benefits with the date and reference number, lists each date of service with the corresponding CPT code and fee, provides a brief clinical summary establishing medical necessity, and requests processing under the client's out-of-network behavioral health benefits.

Step 5: Submit the claim. Submit the CMS-1500 form, superbill, and cover letter to the claims address identified during benefit verification. Some insurers accept electronic submissions through their provider portals even for out-of-network claims. Keep copies of everything you submit.

Step 6: Track and follow up. Insurance companies have 30 to 45 days to process clean claims in most states. If a claim is not processed within that window, call the claims department with the submission date and service dates to inquire about status. If a claim is denied, review the explanation of benefits (EOB) carefully to determine the reason and whether an appeal is appropriate.

Step 7: Educate your client. Many clients do not understand how out-of-network benefits work. Explain the deductible, the difference between the allowed amount and your fee, the coinsurance split, and the timeline for reimbursement. Setting clear financial expectations prevents misunderstandings and supports the therapeutic relationship.

Common Mistakes

Omitting required information from the superbill. Insurance companies will deny claims if the superbill is missing any required field. The most commonly omitted items are the provider's NPI number, the tax ID, and the place of service code. Use a checklist to verify every superbill before providing it to the client.

Using the wrong CPT code for the session duration. CPT 90834 covers 38 to 52 minutes of psychotherapy, and CPT 90837 covers 53 minutes or longer. Billing 90837 for a 45-minute session is incorrect coding and can result in claim denial or audit. Document the exact start and stop time of therapy in your notes.

Not verifying benefits before treatment begins. Clients often believe they have out-of-network coverage when their plan does not include it, or they may not realize they have a separate, higher deductible for out-of-network services. Verifying benefits upfront prevents the client from being surprised by a denial.

Mismatched diagnosis codes. The ICD-10 code on the superbill must match the diagnosis documented in the clinical record. If the progress note documents adjustment disorder but the superbill lists major depressive disorder, the claim may be flagged for inconsistency.

Failing to include medical necessity language. Reimbursement request letters that only describe symptoms without connecting them to functional impairment and treatment necessity are weaker submissions. Always describe how the diagnosis affects the client's daily functioning and why the specific treatment is required.

Sending claims to the wrong address. Many insurers have separate claims addresses for behavioral health versus medical claims, and sometimes separate addresses for in-network versus out-of-network claims. Sending a claim to the wrong address delays processing by weeks or months.

Not appealing denied claims. Many out-of-network claims are denied on first submission due to administrative errors or missing information. A significant percentage of denials are overturned on appeal. Always review the denial reason and resubmit with corrected or additional information when appropriate.