TURNWELL MENTAL HEALTH OF SOUTH DAKOTA, PC
NPI 1639015993
Clinic/Center - Rehabilitation, Substance Use Disorder in Sioux Falls, SD

NPI Status: Active since April 28, 2026

Contact Information

4308 S ARWAY DR
SIOUX FALLS, SD
ZIP 57106
Phone: (605) 573-2000

NPI Profile Information
Primary Taxonomy
Secondary Taxonomies
Authorized Official
CLIA Information
NPI Validation
Other Providers Same Location
Frequently Asked Questions

Organization
Clinic/Center
Rehabilitation, Substance Use Disorder
CLIA Number: 43D2334748
CLIA Cert. Type: Physician Office
CLIA Exp. Date: 11-30-2027

About TURNWELL MENTAL HEALTH OF SOUTH DAKOTA, PC

This page provides the complete NPI Profile along with additional information for Turnwell Mental Health Of South Dakota, Pc, a provider established in Sioux Falls, South Dakota operating as a Clinic/center, focusing in rehabilitation, substance use disorder . The healthcare provider is registered in the NPI registry with number 1639015993 assigned on April 2026. The practitioner's primary taxonomy code is 261QR0405X. The provider is registered as an organization and their NPI record was last updated April 2026. The authorized official of this NPI record is Priyanka Gandhi (Vp Growth)

NPI: 1639015993
Provider Name: TURNWELL MENTAL HEALTH OF SOUTH DAKOTA, PC
Entity Type: Organization
Location Address: 4308 S ARWAY DR SIOUX FALLS, SD 57106
Location Phone: (605) 573-2000
Mailing Address: 4308 S ARWAY DR SIOUX FALLS, SD 57106
Is Sole Proprietor?: No
Is Organization Subpart?: Yes
Enumeration Date: 04-28-2026
Last Update Date: 04-28-2026
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Location Map

Specialty - Primary Taxonomy

The NPI enumerator requires providers to submit at least one taxonomy code. A taxonomy code is a unique 10-character code that describes the healthcare provider type, classification, and the area of specialization. There could be only one primary taxonomy code per NPI record. For individual NPIs the license data is associated to the taxonomy code.

Classification: Clinic/Center Rehabilitation, Substance Use Disorder
Taxonomy Code: 261QR0405X
Type: Ambulatory Health Care Facilities

Secondary Taxonomies

The provider has reported to the NPI enumerator additional taxonomy codes. Multiple taxonomy codes may represent subspecialties or other areas of specialization the provider maybe licensed to practice.

No.	Taxonomy Code	Type	Classification / Specialization	License No. (State)
1	261QM0801X	Ambulatory Health Care Facilities	Clinic/Center Mental Health (Including Community Mental Health Center)

Authorized Official

The authorized official is the designated individual with the legal authority to make changes to the provider’s official NPI record. For organizations, the authorized official must be a general partner, chairman of the board, CEO, CFO or a direct owner holding at least a 5 percent stake in the medical organization.

Authorized Official Name: PRIYANKA GANDHI
Authorized Official Title: VP GROWTH
Authorized Official Phone: (469) 765-0328

CLIA Information

The Clinical Laboratory Improvement Amendments (CLIA) of 1988 applies to facilities or sites that test human specimens for health assessment or to diagnose, prevent, or treat disease. The CLIA Program sets standards for clinical laboratory testing and issues certificates. The NPI / CLIA crosswalk information for this NPI number is:

CLIA Number: 43D2334748
Facility Type: Physician Office
Certificate Effective Date: December 01, 2025
Certificate Expiration Date: November 30, 2027
Laboratory Director: KRISTEN WINTERRINGER
Certificate Type: Certificate of Waiver
Certificate Type Description: This CLIA certificate is issued to Turnwell Mental Health Of South Dakota, Pc to perform only waived tests. CLIA defines waived tests as simple tests with a low risk for an incorrect result. Waived tests include certain tests listed in CLIA regulations, tests cleared by the FDA for home use and tests approved by the FDA for waived status and that meet CLIA waiver criteria.

NPI NPI Number Validation

How NPI Validation Works

The NPI validation process uses the ISO-standard Luhn algorithm, a mathematical "handshake", to ensure that a provider's 10-digit ID is authentic and free of common typing errors.

To verify the NPI 1639015993, we treat the final digit (3) as the Check Digit—the target answer we need to reach. The process begins by taking the first nine digits and adding a constant value of 24, which accounts for the "80840" prefix required for all U.S. health identifiers. We then double every other digit starting from the right and sum the individual digits of those results together. For this specific NPI, that total comes to 67. The final step is to find the difference between that total and the next multiple of ten (70 - 67 = 3).

Digit-by-digit view

Use the first nine digits for the calculation. Starting from the right, double every other digit. The last digit is the check digit and is not part of the calculation.

Pos 1

Doubled → 2

Pos 2

Unchanged

Pos 3

Doubled → 6

Pos 4

Unchanged

Pos 5

Doubled → 0

Pos 6

Unchanged

Pos 7

Doubled → 10 → 1 + 0

Pos 8

Unchanged

Pos 9

Doubled → 18 → 1 + 8

Check

Target digit

Regular digit Doubled digit Check digit

Step 1: Double every other digit from the right

Starting with the rightmost digit of the first nine digits, double every other value. If doubling creates a two-digit number, add those digits together.

1 → 2 3 → 6 0 → 0 5 → 10 → 1 9 → 18 → 9

Step 2: Add all digits plus the NPI constant

Add the transformed values, the unchanged digits, and the constant 24.

2 + 6 + 6 + 9 + 0 + 1 + 1 + 0 + 9 + 1 + 8 + 24 = 67

Step 3: Find the amount needed to reach the next multiple of 10

The next multiple of ten after 67 is 70. The difference is the calculated check digit.

70 - 67 = 3

This NPI is valid

The calculated check digit is 3, which matches the last digit of 1639015993.