Claim forms
Superbill vs CMS-1500: what is the difference?
Both documents carry the same codes, and that is where the similarity ends. One is a claim a provider files with a payer; the other is a receipt a client attaches to their own claim.
Quick answer
The CMS-1500 is the standard paper claim form a provider or billing service files with a payer for professional services; its electronic equivalent is the ASC X12 837P transaction. A superbill is an itemized receipt the provider gives the client, who attaches it to their own member claim form. Both use the same data (NPI, tax ID, CPT, ICD-10-CM, place of service, fees), but only the CMS-1500 is a claim filed by the provider.
Updated · Sources are listed at the end of the page.
Last reviewed October 2026. General information for out-of-network therapists, not legal or billing advice. Payer rules change — confirm with the payer before you bill.
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Run a free checkThe short version
The two differ in who files, who is paid and how strict the format is:
| CMS-1500 | Superbill | |
|---|---|---|
| What it is | A claim form | An itemized receipt |
| Who submits it | The provider or a billing service | The client, with the plan’s member claim form |
| Who is usually paid | The provider, when benefits are assigned | The client |
| Format | Standard form (version 02/12) or the 837P electronic claim | No standard layout |
| Diagnosis codes | Up to twelve in item 21, lettered A–L | As many as the plan needs |
Where the fields line up
A good superbill carries the information a plan would otherwise read from the claim form. Here is where each superbill field lives on the CMS-1500, using the item numbers in CMS’s own instructions:
| Superbill field | CMS-1500 item |
|---|---|
| Client name and date of birth | Items 2 and 3 |
| Member ID | Item 1a |
| Diagnoses (ICD-10-CM) | Item 21, lines A–L |
| Date of service | Item 24A |
| Place of service | Item 24B |
| CPT code and modifiers | Item 24D (room for four modifiers) |
| Diagnosis pointer | Item 24E |
| Fee and units | Items 24F and 24G |
| Rendering provider NPI | Item 24J |
| Tax ID | Item 25 |
| Provider signature | Item 31 |
| Billing provider and NPI | Items 33 and 33a |
When a therapist files a CMS-1500 instead
In-network therapists file claims themselves, almost always electronically as an 837P through a clearinghouse or their practice software. Some out-of-network therapists also file on the client’s behalf as a courtesy. Medicare has its own enrollment and claim rules, so a therapist who sees Medicare clients should not rely on a superbill workflow without checking them.
The paper form itself is printed in red OCR “dropout” ink so that it can be scanned, and CMS’s instructions say photocopies are not acceptable for Medicare. A superbill has no such rule: any clear, legible PDF that carries the required fields will do, as long as the plan accepts itemized bills from members.
Why out-of-network therapists hand over a superbill
Without a contract there is nothing to bill against: the therapist collects the full fee at the time of service and the client deals with the plan. That keeps the practice out of claim follow-up, and the client gets the reimbursement directly.
The trade-off is that the client depends on the superbill being right. A wrong code or a missing NPI comes back to the client, not the therapist, which is why a check before export is worth it.
Can the client send a CMS-1500?
Most commercial plans ask members to use their own member claim form with an itemized bill attached, and some accept the superbill alone through the portal. Requirements vary, so confirm with the payer which form the plan wants before the first submission.
Diagnosis pointers: the field that trips people up
On both documents each service line points at a diagnosis by letter. Medicare’s CMS-1500 instructions ask for one pointer letter per line, the primary diagnosis for that service; other payers allow more. On a superbill, the important thing is that every letter used actually has a code next to it.
Superbill keeps four diagnosis slots, A to D, and blocks an export when a line points at an empty slot. It also checks CPT against session length, telehealth POS and modifiers, the NPI check digit and the age of each date of service, all in your browser.
The app only sends your license key and a device id to our license check (which asks Creem) — no patient or practice data ever leaves your browser.
What the free check catches
- CPT vs. session length (90832 = 16–37 min, 90834 = 38–52, 90837 = 53+; these codes require at least 16 minutes)
- Telehealth POS 02 / 10 vs. POS 11, and modifier 95 pairing
- Diagnosis pointers A–D that don’t resolve to a code on the client
- NPI format and check digit, TIN, member ID, units, signatures
- DOS age against the 60 / 90 day timely-filing warnings