MICHAEL L KORTHALS
NPI 1679767339
Optometrist in Mason City, IA
About Michael L Korthals NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MICHAEL L KORTHALS (NPI 1679767339) is a healthcare organization registered as an optometrist in Mason City, Iowa and active in the NPI registry since September 2007. The organization lists Mike L Korthals, Owner, as its authorized official.
NPPES Registry Identity
Specialties & Licenses
Other Names 1
Other Identifiers 3
Group Practice 1
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, revalidation and the clinicians who bill Medicare through this organization, from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Michael L Korthals is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Revalidation Due Date
Revalidation due by December 31, 2026
Medicare-enrolled providers and suppliers confirm their enrollment information with CMS on a set cycle, every 5 years for most and every 3 years for medical equipment suppliers. CMS sets the due date for each enrollment.
Clinicians Billing Medicare Through This Organization
2Medicare enrollment records show 2 clinicians reassign Medicare billing to Michael L Korthals, which bills Medicare for the services they deliver. Of these, 1 practice at this address. They are listed nearest first.
Clinicians, nearest first (2)
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Medical Equipment Supplier Medicare DMEPOS 2
Medicare supplier enrollment and the product categories Dr Korthals And Associates carries, from the Medicare DMEPOS supplier directory.
Dr Korthals And Associates
DMEPOS supplier · Mason City, IAOperated by Clear Lake Optics CorpAccepts Medicare assignment
Dr Korthals And Associates agrees to accept the Medicare-approved amount as full payment for covered equipment and supplies. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Product Categories
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 Clear Lake Optics Corp's NPI number?
The NPI number for Clear Lake Optics Corp is 1679767339. It was assigned to this organization in the NPPES registry on September 5, 2007. The provider is doing business as Michael L Korthals.
Where is Clear Lake Optics Corp located?
Clear Lake Optics Corp is located at 422 S Pierce Ave Ste 100A, Mason City, IA 50401. The listed phone number is (641) 424-0780.
What is Clear Lake Optics Corp's specialty?
The primary specialty registered for this NPI is Optometrist with taxonomy code 152W00000X.
Is Clear Lake Optics Corp enrolled in Medicare?
Yes. Clear Lake Optics Corp is registered in the Medicare PECOS enrollment system.
When is Clear Lake Optics Corp's Medicare revalidation due?
According to the CMS Revalidation Due Date List (October 2026 release), the Medicare DME enrollment for this organization (Iowa, Physician - Optometrist) is due for revalidation by December 31, 2026. Medicare providers and suppliers revalidate their enrollment every 5 years, and medical equipment suppliers every 3 years. Confirm current requirements with your Medicare Administrative Contractor.
How many clinicians bill Medicare through Clear Lake Optics Corp?
According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Optometry, reassign their Medicare billing to Clear Lake Optics Corp. A 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 the clinician's services. Of these, 1 practice at this address. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Does Clear Lake Optics Corp accept Medicare assignment for medical equipment?
Yes. As a Medicare medical equipment supplier, Dr Korthals And Associates accepts Medicare assignment: the supplier accepts the Medicare-approved amount as payment in full for covered equipment and supplies.
What insurance does Clear Lake Optics Corp accept?
Health plans from Ambetter Health, Ambetter Health of Delaware, Ambetter from NH Healthy Families, Ambetter from Sunflower Health Plan and Oscar Insurance Company list Clear Lake Optics Corp 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 Clear Lake Optics Corp was last updated on December 14, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.
# Michael L Korthals · NPI 1679767339
Optometrist organization in Mason City, Iowa. Organization record, active in the CMS NPPES registry since September 5, 2007.
## Identity
- **NPI:** 1679767339 (Entity type: Organization)
- **Enumerated:** September 5, 2007
- **Primary specialty:** Optometrist · taxonomy 152W00000X
- **Legal business name:** Clear Lake Optics Corp
- **Organization subpart:** No
- **Authorized official:** Mike Korthals, OWNER
## Practice location
- **Address:** 422 S PIERCE AVE STE 100A, Mason City, IA 50401-2709
- **Phone:** (641) 424-0780 · **Fax:** (641) 424-2345
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Medicare revalidation due:** December 31, 2026 (DME, Iowa, Physician - Optometrist) · CMS Revalidation Due Date List, October 2026 release
- **Clinicians billing through this organization:** 2 clinicians (Optometry) reassign Medicare billing to this organization (form CMS-855R); 1 practice at this address · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** December 14, 2023
- **Other identifiers:** Other DB8928 (IA); Medicaid 1204016 (IA); Other 35096 (IA)
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Source: [NPI Profile](https://npiprofile.com/npi/1679767339) · Data from the CMS NPPES public registry.