DR. WILLIAM TERRY ALLEN O.D.
NPI 1891876603
Optometrist - Corneal and Contact Management in Charleston, SC

NPI Status: Active since October 18, 2006

Contact Information

3951 W ASHLEY CIR
CHARLESTON, SC
ZIP 29414
Phone: (843) 852-0075
Fax: (843) 852-0600

NPI Profile Information
Primary Taxonomy
NPI Validation
Other Providers Same Location
Frequently Asked Questions

Individual
Male
Optometrist
Corneal and Contact Management

About WILLIAM ALLEN

This page provides the complete NPI Profile along with additional information for William Allen, a provider established in Charleston, South Carolina with a medical specialization in Optometrist, focusing in corneal and contact management . The healthcare provider is registered in the NPI registry with number 1891876603 assigned on October 2006. The practitioner's primary taxonomy code is 152WC0802X with license number 1217 (SC). The provider is registered as an individual and his NPI record was last updated 19 years ago.

NPI: 1891876603
Provider Name: DR. WILLIAM TERRY ALLEN O.D.
Gender: Male
Entity Type: Individual
Location Address: 3951 W ASHLEY CIR CHARLESTON, SC 29414
Location Phone: (843) 852-0075
Location Fax: (843) 852-0600
Mailing Address: 3951 W ASHLEY CIR CHARLESTON, SC 29414
Mailing Phone: (843) 852-0075
Mailing Fax: (843) 852-0600
Is Sole Proprietor?: Yes
Enumeration Date: 10-18-2006
Last Update Date: 07-08-2007
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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: Optometrist Corneal and Contact Management
Taxonomy Code: 152WC0802X
Type: Eye and Vision Services Providers
License No.: 1217
License State: SC
Taxonomy Description: The professional activities performed by an Optometrist related to the fitting of contact lenses to an eye, ongoing evaluation of the cornea's ability to sustain successful contact lens wear, and treatment of any external eye or corneal condition which can affect contact lens wear.

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 1891876603, 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 → 18 → 1 + 8

Pos 4

Unchanged

Pos 5

Doubled → 16 → 1 + 6

Pos 6

Unchanged

Pos 7

Doubled → 12 → 1 + 2

Pos 8

Unchanged

Pos 9

Doubled → 0

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 9 → 18 → 9 8 → 16 → 7 6 → 12 → 3 0 → 0

Step 2: Add all digits plus the NPI constant

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

2 + 8 + 1 + 8 + 1 + 1 + 6 + 7 + 1 + 2 + 6 + 0 + 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 1891876603.