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Using Your NPI in HIPAA Standard Electronic Transactions FAQs for Health Care Providers

Federal regulations require you to submit HIPAA standard electronic transactions with only your NPI number. Additional information on this requirement follows.


Which HIPAA standard electronic transactions must include the NPI?

  • Claim
  • Encounter
  • Eligibility
  • Claim status inquiry
  • Electronic remittance advice (ERA)
  • Precertification add
  • Referral add
  • NCPDP – Pharmacy

How do I use my NPI?
Health care providers must use their NPIs on electronic transactions adopted by the Health Insurance Portability and Accountability Act of 1996 (HIPAA). Additionally, health care providers need an NPI so they can be identified on electronic transactions performed by other entities. For example, pharmacies must use the NPI of the prescribing physician to submit a claim.

Also, health care providers need the NPIs of referring physicians to submit their own claims electronically. And hospitals need the NPIs of admitting and attending physicians to submit electronic claims to a health plan. We strongly urge providers to share their NPIs with these other entities.

Tips on using organizational NPIs in electronic transactions 

If you are not using your NPI in electronic transactions, contact your EDI vendor to find out how to begin including it. If you use a web-based solution, refer to that website for information.

If you submit electronic transactions using computer software, contact your computer system vendor support area for assistance.

Does the NPI replace the tax ID number?

The billing provider's tax ID number (TIN) and NPI are always required on claims. Any other providers identified on the claim, such as rendering provider or service facility, must be identified with their NPI only. The TIN should not be included.

For eligibility, claim status inquiry, referral and precertification, only the NPI is used. We must have the provider's NPI in our provider database.

Is Aetna maintaining old provider ID numbers and generating new ones?

Yes. We continue to maintain both sets of provider ID numbers. They are needed for other processes.

Are providers allowed to send other identification numbers, such as PIN, PVN and TIN, in electronic transactions?
To be compliant with the regulations, covered entities must use the NPI of any health care provider (or subpart) that has been assigned an NPI to identify that health care provider in HIPAA standard transactions. The use of other IDs is permitted only to identify an entity or individual "as a taxpayer" using the TIN (for example, Social Security number or employer identification number (EIN)). This exception applies only to billing providers in claims and to payees in remittance advices. An NPI also must be used to identify covered health care providers "as providers" in these situations.

Other identification numbers may be used in certain situations:

  • Providers acting in another role, such as an information submitter or receiver, or as a utilization management organization.
  • Non-covered health care providers. For example, a referring provider who does not conduct any electronic transactions is a non-covered provider who may have chosen not to obtain an NPI.
  • Individuals and entities who are not considered health care providers (also known as atypical providers). Atypical providers are persons or groups whose services may be paid for by health benefits plans but who do not directly provide health care. Some common examples include:
    • Personal care workers (for example, aides providing assistance with daily living)
    • Non-medical living arrangements (for example, assisted living, certified family homes, boarding homes, supervised independent living and community residential facilities)
    • Non-emergency transportation providers (for example, taxi services)
  • Entities that administer health benefits but do not directly provide health care, such as:
    • Other health plans
    • Independent practice associations (IPAs)

I submit electronic transactions, but I am not eligible for an NPI. How do I notify Aetna?
Submit an NPI Exemption Notification Form

My organization has multiple NPIs. Which should I use in transactions?
Tips on using organizational NPIs in electronic transactions

Claims & encounters

Does the NPI replace the tax ID number on claims?

The billing provider's tax ID number (TIN) and NPI are always required on claims. Any other providers identified on the claim, such as rendering provider or service facility, must be identified with their NPI only. Their tax ID number should not be included.

Has the NPI changed the way Aetna pays claims and to whom?
No, the NPI did not cause any change to claims adjudication. We use the billing provider tax ID number and provider name and address. The NPI also can be used to identify the appropriate provider.

Does Aetna require the NPI on paper claims?
Regulations require the use of NPIs on electronic transactions. We recommend you send NPIs on paper claims, but we do not require it.

We also accept the use of legacy ID numbers on paper claim forms, but we do not require them. To ensure timely and accurate payment, we recommend that paper forms be completed with either the NPI or the legacy ID.

Does Aetna require the referring physician's NPI on claims?
No. Although we do not require this information for claims adjudication, it may be necessary for you to send it in order to comply with HIPAA regulations.

How is Aetna processing claims that were previously submitted with Medicare OSCAR numbers?

Note: OSCAR numbers, commonly referred to as UPIN or MPN, are six-digit Medicare provider numbers issued to facilities.

To comply with the regulations, use of a Medicare provider number is not permitted on electronic claims. Because of this, we require an NPI, or an NPI and taxonomy code, on institutional claims where we required the submission of a Medicare provider number. Depending on your current set-up, you may or may not be required to submit a taxonomy code to Aetna.

Institutional providers that currently bill Medicare for subparts are required to use taxonomy codes on their claims to Aetna. All other providers are encouraged to use taxonomy codes to help ensure accurate identification, but taxonomy codes are not required.

When a provider cannot send claims electronically, the billing facility taxonomy code should be formatted on the UB-04 paper claim form in field 81cc, preceded with the qualifier B3.

Another payer has notified me that in addition to my NPI, I must submit a different tax ID number on my claims. Should I make the same change in my Aetna claims submissions?
Some providers have multiple tax ID numbers, for example, SSN and EIN or multiple EINs. We are aware that other payers, such as Medicare, have asked some providers to submit claims with a different tax ID number than they used in the past. However, if you make changes to the tax ID number on your Aetna claims, it may affect our ability to process your claims in a timely manner.

If you want to change your tax ID number for Aetna, you can communicate this change as you do any other demographic update by doing one of the following:

  • Contacting our Provider Service Center
  • Contacting your network account manager
  • Utilizing the “Provider Data Maintenance” function from our provider portal

My claim was rejected for missing “Billing Provider” NPI. What action do I need to take on these claims to have them processed?
For claims that reject for National Provider Identifier, use the NPI as the primary ID for the Billing Provider and resubmit electronically.

What error codes will I see if my claim submissions reject for no NPI?

Depending on the format of your vendor's claim status report, you may see codes as listed below and/or text similar to that below:

Code Text
A3 -- Acknowledgement/Returned as unprocessable claim. The claim/encounter has been rejected and has not been entered into the adjudication system.
562 -- National Provider Identifier (NPI)
85 --  Billing Provider

Remittance advice

Does Aetna include NPIs on Explanation of Benefits (EOB) formats other than the electronic remittance advice (ERA)?
Only electronic remittance advices include NPIs at this time.

Is the NPI from the claim included on the payee's electronic remittance advice (ERA), or does Aetna derive the NPI from its internal database?
ERAs include the billing provider's NPI at the payee level unless you request otherwise. To reduce the number of ERAs and EFTs you receive, you can request that the payee NPI on the ERA be an NPI you shared with us. If you choose this “override” option, the ERA will still include the billing provider’s NPI, but it will be at the subgroup level, rather than the payee level.

See more information on ERAs     

If an electronic remittance advice (ERA) can have a different payee NPI than what was submitted on the claim, how can I tell which claim the ERA is responding to?
The submitter's claim number (from CLM01 in an 837 EDI claim) is returned in the CLP01 element in the 835 ERA, and this is not affected by the NPI regulations or related changes. The 835 ERA implementation guide states the following about the CLP01: "This data element is the primary key for posting the remittance information into the provider's database. We also recommend that it be used for that purpose rather than matching by provider IDs." Matching remittances to claims using the provider ID is normally not necessary.

Do new agreements need to be signed for electronic funds transfer (EFT) as a result of the NPI?

Other electronic transactions

Does the NPI replace the tax ID number on eligibility, claim status inquiry, referral and precertification transactions?
For eligibility, referral and precertification transactions, federal regulations require submission of the provider's NPI number unless the provider is not considered a health care provider as defined under HIPAA.

For claim status inquiry, NPI is required in the servicing provider field (it should be the same NPI that was submitted on the claim you are inquiring about), but the billing provider ID can be an NPI, Tax ID or PIN/PVN.

What should I do if I get an error message when I try to transmit my NPI in an eligibility, claim status inquiry, referral or precertification transaction?

You should confirm that we have received and loaded your NPI into our database. You can confirm that your NPI is in our system by logging in to our provider portal. From the home page, select My Providers > Provider Data Management. Select the business from the list, then click on the tabs to manage the data for the business and providers in the business, including NPIs.

How does NPI affect the referral inquiry and precertification inquiry transactions?

Although the referral inquiry and precertification inquiry transactions are not covered by the regulations, we can process them using the NPI as the provider identifier.

When authorization details are returned in response to these inquiries, the providers will be identified by NPI (if one is available in our database).

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