A CID number and an EIN are two different identifiers your business needs for two different governments. The CID, or corporate identification number, is assigned by your state’s Secretary of State when it approves your formation documents, and it identifies your entity in state records. The EIN, or Employer Identification Number, is a nine-digit federal number the IRS issues for tax purposes. You get the CID first, then the EIN.
What Each Number Is
Your CID is a state-level identifier tied to your legal existence as a business entity. Depending on the state, it may be called a corporate identification number, entity number, control number, document number, filing number, or charter number. Same purpose in every case: it permanently identifies your business in state records and distinguishes it from every other registered entity. Formats vary. Some states use six digits, some nine or twelve, some mix in letters. The number stays with your business for its entire existence, through name changes, mergers, and changes in ownership.
Your EIN is a nine-digit federal number issued by the IRS. You use it to pay federal taxes, hire employees, and open business bank accounts.1Internal Revenue Service. Get an Employer Identification Number
A third number sometimes gets tangled in with these two: a state tax ID, issued by your state’s department of revenue for state tax obligations like income withholding or sales tax collection.2U.S. Small Business Administration. Get Federal and State Tax ID Numbers It’s separate from your CID, even though both come from the state.
Which One You Get First and Why
Form your entity at the state level first. The CID is generated when that happens. Then apply for the EIN. The IRS specifically advises forming your entity at the state level before applying, because your EIN application may be delayed otherwise.1Internal Revenue Service. Get an Employer Identification Number The order isn’t a matter of preference. Your legal entity has to exist before the IRS attaches a tax identifier to it.
How You Get Each One
You don’t file a separate application for a CID. The number is generated automatically when the Secretary of State’s office processes and approves your formation documents. For a corporation, those are articles of incorporation. For an LLC, articles of organization. For a limited partnership, a certificate of limited partnership. File the correct document, pay the filing fee, and the state assigns your number.
Filing fees for initial formation vary widely by state and entity type. Expect anywhere from $45 to over $500, with national averages around $125 to $140. Most states now accept online filings, which are processed faster than paper. Online filings often return your entity number and confirmation within a few business days. Mailed documents can take several weeks.
Once your entity is on record, apply for your EIN directly with the IRS. It’s free and can be obtained online in minutes. Be wary of third-party websites that charge a fee for this service; they’re offering something the IRS gives away.
When You Use Your CID vs. Your EIN
Your CID comes up in your dealings with the state. The most routine use is annual report filing. Most states require business entities to file an annual or biennial report updating the state on your current address, officers or managers, and registered agent. These reports are filed using your entity number as the primary identifier, and the state’s online portal typically requires it to log in.
You’ll also need your CID when:
- Amending your articles of incorporation or organization
- Changing your registered agent
- Merging with another entity
- Converting from one entity type to another
- Dissolving the business
- Paying franchise taxes and other business-level state taxes
Use the wrong number, or let your information fall out of date, and payments can be misallocated to the wrong entity. That creates penalties and headaches with the state’s revenue department.
Your EIN, by contrast, is what the federal government and most banks want to see. It’s on your federal tax filings, payroll paperwork, and the account-opening forms at your bank. If a vendor sends you a W-9, the number that goes on it is your EIN, not your CID.
Looking Up a Lost CID
If you’ve misplaced your CID, the fastest path is your state’s Secretary of State business search tool. Every state maintains a free, publicly accessible online database where anyone can look up registered entities. You can typically search by business name, entity number, registered agent name, or officer name. The search results display your entity number along with your filing date, current status, and registered agent information.
If online records don’t resolve the issue, call the Secretary of State’s office directly. Have your exact legal business name and approximate formation date ready, and staff can pull up the record. For businesses formed before states digitized their records, you may need to request a certified copy of your original formation documents, which typically costs a small fee.
A lost EIN is a separate recovery process handled through the IRS, not the state; the CID lookup only surfaces the state number.
Keeping Both Numbers Safe
Business identity theft is a growing problem, and your CID and EIN are both among the pieces of information thieves use. Fraudsters can file false documents with the Secretary of State to alter your business records, change your registered agent, or even dissolve your entity. They can also use a stolen EIN to file fraudulent tax returns or establish credit in your business’s name.3Internal Revenue Service. Tax Practitioner Guide to Business Identity Theft
Warning signs include IRS notices about employees you never hired, tax return rejections because a return was already filed under your EIN, or unexpected changes appearing in your Secretary of State record. If you suspect someone has used your EIN fraudulently, contact the IRS immediately using the information on any notice you received.3Internal Revenue Service. Tax Practitioner Guide to Business Identity Theft For fraudulent state filings, contact your Secretary of State’s office to dispute the changes and flag your account.
Periodically checking your business’s record on the Secretary of State’s website is the simplest preventive step. If your state offers email alerts when filings are made against your entity, sign up. Catching unauthorized changes early is far easier than unwinding the damage months later.