SOS ID

An SOS ID is the number a Secretary of State or similar filing office uses to identify one business record. The label and the format change from state to state.

An SOS ID is the number a Secretary of State or equivalent filing office assigns to a business record so that the record can be found and referenced without ambiguity. It is not a nationwide standard: each state picks its own label and its own format, and a few states show the number without any label at all. “SOS ID” is the everyday name people use for all of them.

What ten states call it

The table below shows the number as it appears on each state’s official register, read from the live record of a well-known company on October 8, 2026. The screenshots further down show the same records.

State	Label on the record	Example (company, number)	Format seen	Official search
Texas	Texas SOS File Number	Dell Technologies Inc., 0806671479	10 digits	Comptroller franchise tax account status
Delaware	File Number	Walmart Inc., 732109	6 digits on this record; newer entities have 7	Division of Corporations entity search
New York	DOS ID #	International Business Machines Corporation, 30059	digits only, length varies with age	Department of State public inquiry
Florida	Document Number	Publix Super Markets, Inc., 112252	6 digits on this 1921 record; newer records use a letter prefix and 11 digits (L for LLC, P for profit corporation, F for foreign)	Sunbiz search by entity name
Idaho	no label; shown in parentheses after the name	Micron Technology, Inc., 4070373	7 digits	SOSBiz business search
Washington	UBI#	Microsoft Corporation, 600 413 485	9 digits in groups of three	Corporations and Charities Filing System
Kentucky	Company ID	Humana Inc., 0154092	7 digits with leading zero	Business entity search
Tennessee	Control No.	FedEx Corporation, 000346608	9 digits with leading zeros	Business entity search
Louisiana	Charter Number	Walmart Inc., 29504510F	8 digits and a trailing letter	Commercial database search
Wyoming	Filing ID	Walmart Inc., 1989-000256368	year, hyphen, 9 digits	Business Center filing search

Three things stand out. The same company carries a different number in every state where it is registered: Walmart is 732109 in Delaware, 29504510F in Louisiana and 1989-000256368 in Wyoming. Formats drift inside one state as the register ages, which is why a 1921 Florida record has six digits and a 2023 one has twelve characters. And Washington’s UBI is a statewide business identifier shared with other agencies, not a number the Secretary of State owns, even though it is the number its register shows.

The number on the official record

Each screenshot is the official state register, captured on October 8, 2026. The red box marks the identifier. Records change, so treat these as illustrations and read the live register for a current value.

Texas Comptroller account status page for Dell Technologies Inc. with the Texas SOS File Number row highlighted — Texas: the Comptroller’s free account status page lists the “Texas SOS File Number” separately from the “Texas Taxpayer Number”. Only the first one is the Secretary of State identifier.

Delaware Division of Corporations entity details for Walmart Inc. with the File Number field highlighted — Delaware: “File Number” is the first field on the entity details page. The free view is not a statement of good standing; status costs extra.

New York Department of State entity search results showing the DOS ID column for International Business Machines Corporation — New York: the “DOS ID #” column appears directly in the search results, next to an “Assumed Name ID #” column that identifies a different kind of filing.

Florida Sunbiz detail page for Publix Super Markets, Inc. with the Document Number row highlighted — Florida: “Document Number” identifies the entity on Sunbiz. The “FEI/EIN Number” below it is the federal tax number, not a state identifier.

Idaho SOSBiz business search for Micron Technology with the record number shown in parentheses after the entity name — Idaho: there is no label. The number sits in parentheses after the entity name in both the results list and the record header.

Washington Corporations and Charities Filing System search results showing the UBI column for Microsoft Corporation — Washington: the register shows the “UBI#”, a nine-digit Unified Business Identifier also used by the Department of Revenue and other agencies.

Kentucky business entity search results showing the Company ID column for Humana Inc. — Kentucky: “Company ID” in the results list. An assumed name filed under the same company shows the same ID.

Tennessee business entity search results showing the Control No. column for FedEx Corporation — Tennessee: “Control No.” is the first column of the results and also a search field of its own.

Louisiana Secretary of State commercial database record for Walmart Inc. with the Charter Number row highlighted — Louisiana: “Charter Number” on the detail record. The trailing letter is part of the number.

Wyoming Secretary of State business detail page for Walmart Inc. with the Filing ID field highlighted — Wyoming: “Filing ID” starts with the year of the first filing.

Entity numbers and document numbers are not the same thing

Several states keep two kinds of number: one for the business itself and another for a document filed for that business. A state may use one of these labels for the entity and a similar label for a filing, so always use the exact label shown on the official record, not the label you expect.

North Carolina uses SOSID for the business entity.
Maine uses Charter Number as the constant identifier for an entity.
Colorado keeps an entity ID and a filed document’s document number separate.
Massachusetts keeps an entity identification number and filing numbers separate.
Florida’s “Document Number” is, despite its name, the entity identifier, as the Publix record above shows.

How to find your SOS ID

Open your state’s official business register. The state guides on this site link to each one.
Search for the exact legal name of the business.
Open the full record. In some states the number is already in the results list; in others it is only on the detail page.
Copy the number with the label the register uses, leading zeros and letters included.
If the record also shows filing or document numbers, do not assume they identify the business.

If a form asks for a number you cannot find on the record, follow that form’s instructions or contact the filing office. Do not substitute a number that looks similar.

SOS ID vs. federal tax ID (EIN)

A state registry number is not an Employer Identification Number. The EIN is issued by the IRS for federal tax purposes, and some registers show both side by side, as Florida does. Do not enter an EIN in a state identifier field unless the form specifically asks for it.

Sources reviewed

The ten records in the table and the screenshots were read from the official registers on October 8, 2026:

The following were retrieved and confirmed on August 20, 2026: