An NPI (National Provider Identifier) is a free, 10-digit number CMS issues through NPPES to identify a US health care provider in HIPAA transactions such as claims. Individuals get a Type 1 NPI and organizations get a Type 2. The number never changes, and the digits themselves carry no information about the provider. Look one up for free in the NPPES NPI Registry by number, name, phone or address, check that the record isn't deactivated, and use the Luhn check digit to catch a typo before you search.
Key takeaways
- An NPI is a unique, intelligence-free 10-digit identifier for HIPAA transactions. The digits don't encode a provider's state, specialty or type.
- Individuals get a Type 1 NPI; organizations get a Type 2. A sole proprietor applies as Type 1, and a subpart of an organization can hold its own Type 2.
- It's free and takes about 20 minutes to apply for through NPPES.
- The number itself never changes, even if a provider's name, address or specialty does — but it can be deactivated, so always check the record's status.
- NPPES data is published under the Freedom of Information Act and providers can't opt out, though Social Security numbers and email addresses are never part of the public record.
- Every NPI ends in a check digit calculated with the Luhn formula, which catches a typo before you ever search the registry.
What is an NPI, and why does it matter?
An NPI (National Provider Identifier) is a unique 10-digit number that identifies a US health care provider in HIPAA standard transactions such as claims. CMS issues it free through the National Plan and Provider Enumeration System (NPPES). It never changes, and the digits carry no information about the provider. Individuals get a Type 1 NPI and organizations get a Type 2.
The NPI shows up everywhere in US health care: on claims, prescriptions, credentialing forms and referral letters. That's why so many people need to look one up. Billing teams check them before submitting claims, pharmacies check prescribers, recruiters confirm a clinician's license state, and medical sales teams use NPI data to clean their prospect lists. "NPI number lookup" alone is searched about 18,100 times a month in the US, according to DataCaptive's keyword research.
Look it up now
Need to check an NPI right now? Search by number, name, phone or mailing address with DataCaptive's NPI number lookup, then export the results to your CRM.
Type 1 vs Type 2 NPI
The table below compares what each type covers and who applies for it.
| Type 1 (individual) | Type 2 (organization) | |
|---|---|---|
| Who gets it | Individual health care providers | Health care organizations |
| Examples | Physicians, dentists, nurses, pharmacists, chiropractors, physical therapists | Hospitals, clinics, group practices, laboratories, nursing homes, pharmacies, medical equipment suppliers |
| How many | One per person, for life | Can have several, one per subpart that bills on its own |
| Sole proprietors | Apply as Type 1 | Not applicable |
| Key detail | Stays with the person when they change jobs or states | A hospital's lab, pharmacy and rehab unit may each hold their own NPI |
Two cases trip people up:
Incorporated individuals
A physician who has set up a corporation or LLC may need both: a Type 1 NPI for themselves and a Type 2 NPI for the company, according to the CMS NPI booklet.
Subparts
Parts of an organization that operate separately, such as a hospital's laboratory, may need their own NPI if they run HIPAA transactions on their own. Subparts only apply to Type 2.
Who needs an NPI, and what the number does and doesn't tell you
Every health care provider that is a HIPAA-covered entity must have an NPI, whether it's an individual or an organization. In practice, many providers who never bill electronically get one anyway, because pharmacies and health plans ask for it. It's free and takes about 20 minutes to apply online through NPPES.
What the number itself tells you: nothing
CMS describes the NPI as an "intelligence-free" identifier. The digits don't encode the provider's state, specialty or type. You need the NPPES record for that.
What it isn't
An NPI is not a license. CMS's fact sheet is clear that having one doesn't ensure licensure or credentialing, guarantee payment, or enroll the provider in a health plan. It also doesn't replace Medicare enrollment.
What doesn't change it
A provider keeps the same NPI when their name, address or specialty changes. They must update their NPPES record within 30 days of a change, but the number stays the same. An NPI can be deactivated, though, so a number on an old form may no longer be active.
What the public record shows
CMS has published NPPES data under the Freedom of Information Act since September 2007, and providers with an active NPI can't opt out, according to CMS's data dissemination page. A record typically includes:
- Provider name and credentials (for individuals), or legal business name (for organizations)
- Practice location and mailing addresses, phone and fax
- Taxonomy codes, which describe the provider's specialty
- License number and license state (individuals)
- Authorized official's name, title and phone (organizations)
- Enumeration date, last update date and any deactivation date
Social Security numbers and email addresses are not part of the public record.
How to look up an NPI number
The NPPES NPI Registry (free)
The NPI Registry is CMS's free search tool, updated daily.
- Open the NPPES NPI Registry.
- Search by the 10-digit NPI, or by first and last name for an individual, or organization name for a Type 2.
- Narrow the results with state, city, ZIP code or taxonomy (specialty) if the name is common.
- Open the record and check the enumeration type, primary taxonomy, practice address, phone and the last updated date.
- If you're verifying a provider for billing or credentialing, confirm the record isn't deactivated.
Bulk downloads
If you need to check thousands of providers, the search tool is too slow. CMS publishes a full replacement NPI file every month and weekly incremental files with new NPIs, updates and deactivations, available from the NPPES data dissemination page. Load the monthly file, apply the weekly files, and repeat when the next monthly file comes out.
DataCaptive's NPI lookup
Our NPI number lookup lets you search by NPI, name, phone number or mailing address, then export the results or push them to your CRM. It's built for sales, marketing and recruitment teams that need provider records joined to business contact details, which the federal registry doesn't include.
Export-ready
Search by NPI, name, phone or mailing address, then export the results or push them to your CRM.
How to check that an NPI is valid
Every NPI ends in a check digit, calculated with the Luhn formula (the same one used on credit card numbers). That lets you catch a typo before you search. CMS's check digit documentation uses NPI 1234567893 as its example:
- Take the first nine digits: 1 2 3 4 5 6 7 8 9.
- Starting from the rightmost of those digits, double every other one: 9, 7, 5, 3 and 1 become 18, 14, 10, 6 and 2.
- Add the digits of the doubled numbers (1+8, 1+4, 1+0, 6, 2) to the digits you didn't double (8, 6, 4, 2). That's 43.
- Add 24. This constant stands in for the 80840 prefix that NPIs carry when used on health ID cards. The total is 67.
- Subtract from the next multiple of 10: 70 minus 67 is 3. The tenth digit should be 3, and it is.
A number that passes is well-formed. It doesn't prove the NPI is active or belongs to the person you think it does. For that, check the registry.
Using NPI data for healthcare marketing and recruitment
Clean provider data is the difference between a healthcare campaign that reaches clinicians and one that bounces off closed practices. NPI data helps in three ways:
- Cleaning lists. Match your contacts to NPIs and remove anyone whose NPI has been deactivated or whose practice address has moved.
- Segmenting by specialty. Taxonomy codes let you separate, say, family medicine from cardiology, or nurse practitioners from registered nurses, more reliably than job titles typed into a form.
- Confirming licensure location. Recruiters can see a clinician's license state before they call about a role in another state.
What NPPES doesn't give you is a business email address. That's where our healthcare lists come in. The most requested are nurses, registered nurses, nurse practitioners, surgeons, cardiologists, family medicine physicians and medical directors. If you already have a provider list, our data verification services can check it before your next campaign.
Where HIPAA fits. HIPAA protects patients' health information. Contacting a provider at their practice about a business product, using their public NPPES details and a business email, doesn't involve patient data. Email and phone rules still apply, though: CAN-SPAM for email in the US, and TCPA for calls and texts to mobile numbers. If your company is itself a covered entity or business associate, keep marketing data separate from any patient data you hold. You can read how we verify contact data before it reaches you.
Frequently asked questions
Yes. CMS publishes NPPES data under the Freedom of Information Act, and providers with an active NPI can't opt out. The record includes name, practice address, phone, specialty codes and license details, but not Social Security numbers or email addresses.
It doesn't change when a provider's name, address or specialty changes. It can be deactivated, so always check the record's status.
Nothing. The NPI is free, and the online application through NPPES takes about 20 minutes, according to CMS.
Type 1 is for individual providers such as physicians, nurses and sole proprietors. Type 2 is for organizations such as hospitals, group practices, labs and pharmacies.
An individual can have only one. An organization can have several, for example one for each subpart that bills separately.
No. The NPI is an identifier for HIPAA transactions. It doesn't prove licensure, and it's separate from state license numbers and DEA registration.
Check the tenth digit with the Luhn formula to catch typos, then search the NPI Registry to confirm the number is active and matches the provider.