Updated September 29, 2026.
To file an assumed name (DBA) for an existing Texas LLC or corporation, sign in to SOSPortal, open Business Filings, and start a filing for the existing entity through Manage an Entity Record. Select the assumed-name submission, enter the required information, review it, and pay the $25 state filing fee. The state emails evidence of filing after acceptance.
If you searched for “how to file Form 503 on SOSDirect,” the online route has changed. SOSPortal replaced SOSDirect and SOSUpload for business filings on September 29, 2026. Form 503 is still the state’s assumed name certificate; the current Form 503 instructions direct online filers to enter the information through SOSPortal’s screens. This guide follows the state’s published instructions for an existing entity with an SOS record.
First, confirm whether you file with the state or county clerk
Your business structure determines where to file. “DBA” means doing business as; it does not identify a separate type of business entity.
| Your business | Where the assumed name is filed |
|---|---|
| LLC, corporation, limited partnership, limited liability partnership, professional association, or other covered foreign filing entity | Texas Secretary of State |
| Sole proprietorship or general partnership that is not an LLP | Applicable county clerk or clerks |
The Secretary of State’s assumed-name FAQs explain that county filers generally file in each county where they maintain a business office. If they have no Texas business office, they file in each county where they conduct business. Check the county clerk’s own form, fee, and signature requirements.
An LLC filing its assumed name with the Secretary of State does not also need a county assumed-name filing. Texas eliminated that additional county requirement for these entities in 2019. Listing counties on Form 503 is still required; that field does not create a separate county filing obligation.
For example, if “Cedar Trail Ventures LLC” will operate as “Cedar Trail Coffee,” the LLC is the registrant and “Cedar Trail Coffee” is the assumed name. Filing that DBA does not create another LLC or change the LLC’s legal name.
Gather the information before opening SOSPortal
Use the official Form 503 instructions and linked PDF as your checklist:
| Information | What to prepare |
|---|---|
| Assumed name | The exact name the business will use; it must differ from the entity’s exact legal name |
| Legal entity | The entity’s legal name, entity type, and SOS file number, if assigned |
| Formation jurisdiction | The state or country where the entity was formed |
| Principal office | The entity’s principal office street or mailing address |
| Duration | A term of up to 10 years |
| Counties | All Texas counties, all except specified counties, or only the listed counties, as applicable |
| Authorized signer | The person authorized to execute the certificate for the entity |
Do not enter your own name as the registrant when the business using the DBA is your LLC. The legal entity and the person signing on its behalf have different roles.
How to file Form 503 online in SOSPortal
1. Sign in and open Business Filings
Open the official SOSPortal entry page, review the Rules of Use, and select Access the SOS Portal. Use your SOSPortal account and complete the verification steps. Your former SOSDirect account is a separate account.
Select Business Filings. The filing application opens in another tab. If you are stuck on account creation, login, or verification codes, start with our SOSDirect-to-SOSPortal access guide.
2. Locate the existing entity
Under Start New Filing, choose Manage an Entity Record. Search using the entity’s SOS file number or legal name. Open the correct entity by selecting its file number, then choose Start Submission and the assumed-name filing type.
Check the legal name and file number carefully before proceeding. For an existing LLC’s DBA, you are filing against that LLC’s record. You are not creating a new LLC. The state’s Business Filings Guide illustrates this existing-entity workflow and lists assumed names among the supported filings.
3. Complete the assumed-name information
Enter the information from your checklist, including the assumed name, duration, and counties where it will be used. Follow the online prompts for the authorized signer and any required supporting information.
The September 2026 instructions direct online filers to use the filing screens. Do not assume you must upload the old Form 503 PDF through a separate SOSUpload account. Follow any attachment request in the current filing workflow, and do not attach the state’s instruction pages, duplicate copies, or unnecessary personal identifying information.
4. Preview and pay
Review the proposed filing before checkout. Confirm the DBA spelling, legal entity, duration, counties, and signer. A certificate using the entity’s exact legal name as its assumed name will be rejected.
The base state fee is $25 per assumed name certificate. Online payment is available by ACH or credit card. The state lists a card convenience fee of $0.25 plus 2.25% of total fees. Optional services may increase the total; review the checkout amount before paying.
5. Check the submission and save the filing evidence
Save the payment confirmation and submission tracking number. Open My Submissions to check progress, and select the tracking number for details. A payment receipt is not the same as an accepted filing. The state emails the evidence of filing after acceptance; retain it with the company’s records.
If the submission is rejected, read the reason and follow the portal’s edit-and-resubmit instructions. If you cannot locate a pre-transition filing, check your original receipt and contact the state before submitting and paying again.
Common Form 503 questions
Does filing a DBA protect the name?
An assumed name certificate gives public notice of who is using the name. It does not grant exclusive rights or resolve trademark conflicts. Another business may have the same assumed name on file. A Texas business name search can help you investigate records, but a search result or accepted DBA filing is not trademark clearance.
Do I need a notary?
The Secretary of State’s FAQs say an assumed name certificate filed with that office does not need notarization. County clerk requirements can differ. The certificate still must be executed by a person authorized to act for the registrant.
Can I file several DBAs for one LLC?
Yes. File a separate certificate for each assumed name and pay the applicable fee for each. Multiple DBAs remain names used by the same entity; they do not create separate liability protection for each business activity.
Can I change or renew an existing assumed name certificate?
There is no amendment or correction procedure for an assumed name certificate. A material change requires a new certificate, generally within 60 days of the change. For renewal, file a new certificate during the six months before the existing certificate expires. The maximum term is 10 years. Check the term on your actual certificate rather than assuming every filing lasts the full 10 years.
Can I still file by mail or in person?
Yes. The current instructions allow mail and in-person filings, with payment by check or money order. Mail to P.O. Box 13697, Austin, TX 78711-3697, or deliver to 400 W. 15th St., Austin, TX 78701. Use the current official form and instructions; evidence of a paper filing is mailed to the submitter.
What if I cannot find the entity or assumed-name option?
Check that you are in Business Filings and using the existing-entity route. Search by the SOS file number if a name search produces several similar entities. For an entity without an SOS record, a series LLC filing, or a submission type you cannot locate, ask the Corporations Section at CorpInfo@sos.texas.gov for the correct filing route. Do not select an unrelated submission type simply to get through checkout.
When legal help may be useful
A straightforward assumed-name filing may be something you can complete yourself. Legal advice is more useful when you are deciding which entity should own a brand, adding owners, separating business risks, or addressing a possible name conflict. Massingill’s Texas business formation attorneys can help with those decisions and related filings. Contact us with your entity’s legal name, proposed DBA, and the issue you need to resolve.
Joshua Massingill
Joshua Massingill is an attorney practicing in Austin, Texas. He serves on the Texas State Bar’s Law Practice Management Committee, the Leander Educational Excellence Foundation (LEEF) Board of Directors, and the Success-Werx Board of Advisors. He mentors young entrepreneurs in Leander ISD’s INCubatorEDU program and is active in his church.