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WELBY NIELSEN D.O.
NPI 1962611947
Psychiatry & Neurology - Child & Adolescent Psychiatry in San Luis Obispo, CA

Active since May 22, 2007PECOS EnrolledAccepts Medicare Assignment
1039 MURRAY AVE STE 220, SAN LUIS OBISPO, CA 93405(805) 250-2996(805) 250-2998 Get Directions Write a Review

NPPES record last updated: March 29, 2018. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Welby Nielsen D.o. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

WELBY NIELSEN D.O. (NPI 1962611947) is an individual child & adolescent psychiatry provider in San Luis Obispo, California, licensed in California (20A11177) and active in the NPI registry since May 2007. He is enrolled in Medicare PECOS, maintains a secondary practice location in Chico, and is a graduate of University Of Arizona College Of Medicine (2005).

NPPES Registry Identity

NPI1962611947
Entity TypeIndividualMale
Primary Taxonomy2084P0804X
Provider Legal NameWELBY NIELSENCredential: D.O.
Location Address1039 MURRAY AVE STE 220San Luis Obispo, CA 93405-2058
Mailing Address3835 N Freeway Blvd Ste 100Sacramento, CA 95834-1954 · (916) 576-7900 · Fax (916) 285-0338
Phone(805) 250-2996
Fax(805) 250-2998
Sole ProprietorNo
Medical School CMSUniversity Of Arizona College Of MedicineGraduated 2005
Enumeration DateMay 22, 2007
Last NPPES UpdateMarch 29, 2018
✔ NPI 1962611947 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyPsychiatry & Neurology · Child & Adolescent PsychiatryAllopathic & Osteopathic Physicians
Taxonomy Code2084P0804X
License✔ Licensed in CA · 20A11177
Definition
Child & Adolescent Psychiatry is a subspecialty of psychiatry with additional skills and training in the diagnosis and treatment of developmental, behavioral, emotional, and mental disorders of childhood and adolescence.
Also ListedPsychiatry & Neurology · PsychiatryTaxonomy 2084P0800X · License 20A11177 (CA)
1039 MURRAY AVE STE 220, San Luis Obispo, CA 93405
Open in Google Maps ↗

Secondary Practice Location 1

Location 12561 California Park Dr Ste 300Chico, CA 95928-4208 · Phone (530) 838-4188 · Fax (530) 809-2481

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Welby Nielsen D.o. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID1658549860
PECOS Enrollment IDI20110713000806
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Welby Nielsen reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Mark David Levine, MD Fresno
116 mi
Psychiatry
5100 N 6TH ST, STE 135
Fresno, CA 93710
  • Reassigned Medicare billing, California enrollment
  • Medicare enrollment name: Mark David Levine MD Professional Corporation
  • 329 clinicians in this Medicare group
NPI 1124387097 (559) 490-2067

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Other Providers at the Same Location NPPES 5

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

PETER F. AFSARI D.O.
Psychiatry & Neurology (Psychiatry)
1039 MURRAY AVE STE 220
SAN LUIS OBISPO, CA 93405
San Luis Obispo County (805) 250-2996
ERIC MARTIN BLUMENFELD MD
Psychiatry & Neurology (Psychiatry)
1039 MURRAY AVE STE 220
SAN LUIS OBISPO, CA 93405
San Luis Obispo County (805) 250-2996
AMANDA SELMAN
Nurse Practitioner (Psychiatric/Mental Health)
1039 MURRAY AVE STE 220
SAN LUIS OBISPO, CA 93405
San Luis Obispo County (855) 501-1004
ELIZABETH ZAREK
Marriage & Family Therapist
1039 MURRAY AVE STE 220
SAN LUIS OBISPO, CA 93405
San Luis Obispo County (855) 501-1004
MS. KRISTIN BILLINGSLEY TONEY APRN- NP
Nurse Practitioner (Psychiatric/Mental Health)
1039 MURRAY AVE STE 220
SAN LUIS OBISPO, CA 93405
San Luis Obispo County (855) 501-1004

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Welby Nielsen's NPI number?

The NPI number for Welby Nielsen is 1962611947. It was assigned to this individual provider in the NPPES registry on May 22, 2007.

Where is Welby Nielsen located?

Welby Nielsen practices at 1039 Murray Ave Ste 220, San Luis Obispo, CA 93405. The listed phone number is (805) 250-2996.

What is Welby Nielsen's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Child & Adolescent Psychiatry, with taxonomy code 2084P0804X.

Is Welby Nielsen enrolled in Medicare?

Yes. Welby Nielsen is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Welby Nielsen's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Welby Nielsen reassigns Medicare benefits to Mark David Levine, MD Fresno (Fresno, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Welby Nielsen's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Welby Nielsen was last updated on March 29, 2018. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.