MARY H. DAU O.D.
NPI 1205210374
Optometrist in Katy, TX
About Mary H. Dau O.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARY H. DAU O.D. (NPI 1205210374) is an individual optometrist in Katy, Texas, licensed in Texas (8757TG) and active in the NPI registry since July 2015. She is enrolled in Medicare PECOS, maintains 2 additional practice locations, and is a graduate of Other (2015).
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Locations 2
Group Practice 1
Accepted Insurance
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
Mary H. Dau O.d. 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.
Medicare Billing Reassignment
Medicare enrollment records show Mary Dau reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Katy, TX 77494
- Reassigned Medicare billing, Texas enrollment
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims 3
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 77494 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
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 Mary Dau's NPI number?
The NPI number for Mary Dau is 1205210374. It was assigned to this individual provider in the NPPES registry on July 17, 2015.
Where is Mary Dau located?
Mary Dau practices at 6630 Fm 1463 Rd Ste A400, Katy, TX 77494. The listed phone number is (281) 394-7090.
What is Mary Dau's specialty?
The primary specialty registered for this NPI is Optometrist with taxonomy code 152W00000X.
Is Mary Dau enrolled in Medicare?
Yes. Mary Dau 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 Mary Dau's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mary Dau reassigns Medicare benefits to The Third Sister, PLLC (Katy, TX). 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 Mary Dau's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Mary Dau accept?
Health plans from Anthem Blue Cross and Blue Shield, Blue Cross and Blue Shield of Montana, Blue Cross and Blue Shield of Oklahoma, Blue Cross and Blue Shield of Texas and BlueCross BlueShield of Tennessee and 8 other insurers list Mary Dau as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
When was this NPI record last updated?
The NPPES record for Mary Dau was last updated on February 8, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 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.
# Mary H. Dau, O.D. · NPI 1205210374
Optometrist provider in Katy, Texas. Individual provider, active in the CMS NPPES registry since July 17, 2015.
## Identity
- **NPI:** 1205210374 (Entity type: Individual)
- **Enumerated:** July 17, 2015
- **Primary specialty:** Optometrist · taxonomy 152W00000X
- **State license:** 8757TG (Texas)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 6630 FM 1463 RD STE A400, Katy, TX 77494
- **Phone:** (281) 394-7090
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health
- **Bills Medicare through:** The Third Sister, PLLC (NPI 1881177616, Katy, TX), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2015
## Record status
- **NPPES last updated:** February 8, 2021
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Source: [NPI Profile](https://npiprofile.com/npi/1205210374) · Data from the CMS NPPES public registry.