ADVOCATE NORTHSIDE HEALTH SYSTEM
ADVOCATE NORTHSIDE HEALTH SYSTEM is an organization registered with the National Plan and Provider Enumeration System (NPPES) under NPI 1861774408, based in Chicago, IL. It is classified under Mental Health Clinic/Center (Including Community Mental Health Center).
Getting there
The practice address on file is 913 W WELLINGTON AVE FL 2, Chicago, IL 60657. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 04004 | IL | Mental Health Clinic/Center (Including… primary |
This provider holds licence 04004 issued in IL. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.
What Mental Health (Including Community Mental Health Center) covers
Definition to come... NUCC Health Care Provider Taxonomy, code 261QM0801X
The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.
Full NPPES record
An NPI-2 identifies an organization — a clinic, hospital, group practice, laboratory, or supplier. Individual clinicians working there hold their own NPI-1 numbers separately, so a bill may reference both.
| NPI | 1861774408 valid check digit |
|---|---|
| Entity type | Organization (NPI-2) |
| Enumeration date | Sep 9, 2011 |
| Last updated | Apr 21, 2026 |
| Status | Active |
| Practice address |
913 W WELLINGTON AVE FL 2 Chicago, IL 60657 (873) 843-0200 |
| Mailing address |
PO BOX 70508 Chicago, IL 60673 |
| Other identifiers |
04004
· Medicaid (IL) |
Number check
How the check works, step by step
Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.
| Digit | 8 | 0 | 8 | 4 | 0 | 1 | 8 | 6 | 1 | 7 | 7 | 4 | 4 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 8 | 3 | 1 | 5 | 7 | 8 | 4 | 0 |
Sum = 62 · next multiple of 10 = 70 · check digit = 8 · actual last digit = 8
A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.