Do I Have to Display My Business License or License Number?

By Bill Stilwell · Last reviewed October 17, 2026

The short answer

Display rules come from your state, county, city, and licensing board, not one national rule. Many local business licenses and health permits must be posted where customers can see them. Some states also require license numbers on ads, contracts, and vehicles. California’s contractor board, for example, requires contractors to put their license number on contracts, bids, and advertising. Check every agency that issued you a license and follow the strictest rule.

What this means

There are three common kinds of display rules.

Posting at your place of business. Local business licenses, health permits, and some professional licenses often must be posted where customers can see them. Salons and health providers often must post each worker’s license at their station or room.

License numbers in ads and paperwork. Some states require contractors and certain professionals to include their license number in ads, on websites, on bids, and on contracts. As one example, California’s Contractors State License Board says licensed contractors must include their license number on construction contracts, subcontracts, bid solicitations, and advertising.

License numbers on vehicles. Some states require business name and license number on work vehicles. California, for example, sets size rules for the lettering, and the rules differ by license type.

Workplace posters for employees, like wage and safety notices, are a different topic (see 23.4.6 Required Workplace Posters).

Made-up example: Copper Creek Plumbing gets a new state license. The owner checks the board’s advertising rules and adds the license number to the website footer, the truck doors, the estimate template, and the contract. He also posts his city business license by the front counter and adds the number to the Google Business Profile description.

Why it matters

Fines. Boards can fine you for missing license numbers in ads or on vehicles.
Complaints. Competitors and customers can report you.
Trust. Customers can look up a posted number and see you’re real.
Consistency. A number that matches the state lookup site backs up everything else you say about your business.

Who this applies to

Any licensed business. Contractors, trades, salons, food businesses, and health care providers have the most display rules. Unlicensed businesses should check their local business license, which may still need to be posted.

How to do it

List every license and permit from your requirement matrix (see 9.3 Requirement Matrix).
Read each agency’s display rules. Look for “advertising,” “display,” or “posting” on the board’s website.
Post required licenses at your location where customers can see them. Post individual licenses at each worker’s station if required.
Add license numbers to everything the rules cover: website, ads, estimates, contracts, invoices, and vehicles.
Add your license to your website and profiles even where it isn’t required. Use the same number and format everywhere (see 14.1.10 Credentials).
Update everything at renewal if your number or expiration date changes (see 9.5.6 License and Permit Renewals).
Recheck when you add a new ad channel, like yard signs, social media ads, or a new directory.

What proof to keep

Photos of posted licenses at your location, with the date
Screenshots of license numbers on your website and listings
Photos of vehicle lettering
A sample contract and estimate showing the number
A note of each agency’s display rule and where you found it

Common mistakes

Posting an expired license after renewing and forgetting to swap in the new one.
Leaving the number off new ads, like social media ads or yard signs.
Using a number that doesn’t match the state lookup site, such as an old number or a typo.
Claiming a license you don’t hold, or implying your license covers work it doesn’t. That can break advertising laws (see 11.3.1 Truthful Advertising Claims).
Assuming no rule applies because you work out of a truck.

When to get help from a pro

Your licensing board can tell you exactly what must appear and where. An attorney can help if you receive a citation. Questions to ask:

Where must my license or license number appear: ads, website, vehicles, contracts?
Does social media count as advertising under your rules?
Do my employees need to post their individual licenses?

Bill’s note

[Bill: add a short opinion. For example, why you add license numbers to every contractor website you build, or a client who got a board letter over a missing number.]

If you’d rather have this done for you, SiteSmarty can add your license and credentials to your website and Google Business Profile.

How I did this for SiteSmarty

[Date I did this:]
[What I actually did, step by step: which licenses or registrations SiteSmarty shows, and where]
[What it cost and how long it took:]
[What surprised me or what I’d do differently:]
[Screenshot or photo to add, with private info blurred: website footer, About page, or posted license]
[Result so far:]

Questions people ask

Do I have to post my business license? Often, yes, for local business licenses and health permits. Check each agency that issued you a license.

Do I need my contractor license number on my ads? In some states, yes. California, for example, requires it on advertising, bids, and contracts. Check your state board.

Do I need my license number on my truck? Some states require it. Check your board’s vehicle rules, including lettering size.

Should my license number be on my website? It’s good practice even when it isn’t required. It lets customers check you and keeps your information consistent.

Do employees have to display their licenses? In some professions, like cosmetology, yes. Check your state board.

Audit check

Question: Does the business post and show its license numbers everywhere its agencies require, and do the numbers match the state lookup site?
Pass looks like: Required licenses posted and current. License number on ads, website, vehicles, contracts, and estimates where required. Same number everywhere.
Fail looks like: Expired licenses posted. Missing numbers in ads or on vehicles. Numbers that don’t match the state record.
Evidence to collect: Photos of posted licenses and vehicles, website and listing screenshots, a sample contract, and a state lookup screenshot.

Where this fits

Do this first: 9.5.2 State Licenses, 9.5.6 License and Permit Renewals

Do this next: 9.6.2 Product Regulation

Sources

California Contractors State License Board, "Advertising Guidelines for Contractors" (checked October 17, 2026)
U.S. Small Business Administration (SBA), "Apply for licenses and permits" (checked October 17, 2026)

This page explains general rules and Bill's own experience. It is not legal, tax, or insurance advice. Talk to a qualified professional about your situation.