As a business owner, your reputation depends on the quality and reliability of the components you use in your products or in the merchandise you sell. One way to strengthen your position is to verify that everything you sell is UL certified. With the recently updated version of the Underwriters Laboratories database, you can use the online UL search tool to check the UL-listed numbers on each product and verify their safety status.

What Is a UL Certification Number?

The nonprofit organization Underwriters Laboratories tests products and component parts throughout the electrical and technical industries and places its seal of approval on thousands of products including industrial equipment, lighting components and home appliances.

The mark signifies that each product meets specified national and global safety standards. Consumers generally feel more confident purchasing a product with a UL-listed mark. The UL mark consists of two capital letters (U and L) placed in a circle and a unique four-to-six-digit control or issue number that is placed underneath the circle.

Access the UL Product Database

Gain easy access to the Underwriters Laboratories product-listing database, called Product iQ, by visiting the UL website at You'll need to register in order to activate your free account. The UL online certifications directory is designed to be a helpful resource for corporate entities, but individual consumers may also access the database. There is no cost for basic searches, but more advanced search tools require a subscription.

Search for a UL Number

By entering a UL number, you can verify the safety status of the product it represents. In addition to entering the UL file number, you can search by company, CNN number, assembly number or construction number, among others. This feature allows you to cross-reference parts no matter what information you have on hand.

Additionally, product developers and engineers can search for similar components that meet their specifications if one they want is not UL certified or is no longer available.

Consider a UL Search Tool Subscription  

For businesses that do frequent searches, a subscription to the Product iQ tool will provide additional search tools and features that will save time. Searches can be saved and grouped according to component types and when certain routine searches are required. Additionally, the service provides official certification letters that serve as verification that safety standards are approved for the equipment you use or the parts you sell.

Reasons for a Missing Number

There are several reasons you may be unable to find a UL certification number when you use the UL search tool to look up a specific number. First, check to be sure you have entered the numbers correctly. If that checks out, try searching again using a part or assembly number as a way to cross-reference and search for the component.

If you still cannot find the UL number in the verification database, it is possible that the certification has expired or has been pulled because it no longer meets safety requirements. It is also possible that the certification number has been falsified. Unfortunately, some vendors try to pass off their components as UL certified by forging the UL mark on a product label and creating a fake ID number. This is a key reason for verifying that the components you sell and use are truly certified.

UL Market-Access Configurator

For product developers and manufacturers, Underwriters Laboratories also provides assistance in determining global guidelines and safety requirements for products anywhere in the world. Their interactive map, found at, allows users to target global markets and develop products that will comply with regional standards.