## UL vs ETL on Christmas String Lights: The Logo Is Not the Listing I pulled a pallet of christmas string lights off a customer's receiving dock last January. The box carried a perfectly printed UL logo. The light string inside it was listed. The controller, the power supply, the whole assembly: nothing. Nobody at the buying side had ever asked what the mark was attached to. That gap is where most import complaints start. Here is how to close it before the freight is booked, not after. ## The Mark Is a File Number, Not a Sticker UL, ETL and CSA are all NRTL marks under OSHA's recognition program, and they can certify to the same US standards. A light string tested to ANSI/UL 588 by Intertek carries an ETL mark; the same string tested by UL Solutions carries a UL mark. Same standard, different certifier. So "which logo looks better" is the wrong question, and I get tired of answering it. The right question is what the file actually covers. A listing is a record: a certifier, a file or control number, a product description, a factory location, a standard, and ongoing follow-up. A logo printed on a box is none of that. It is ink. I have watched a supplier mail over a certificate for one model while shipping a sibling model with a thinner cord and a different socket. Same factory, same name plate, different file. The certificate was genuine. It was just not the certificate for the product on the pallet. ## The Factory-Model Mismatch That Kills Listings Listings belong to a design at a specific factory. Change the design after listing and the product can fall outside what was certified: thinner wire gauge, a different bulb base, a controller from another line, or the run moved to a subcontractor plant. The mark has to be applied under the certifier's program, and a seller's brochure is not that program. Two practical failure modes. First, the "similar looking" swap: the quoted model is listed, the replacement is not, and the paperwork travels with the quote instead of the goods. Second, the component trap: the LED string is listed, the adapter is only a recognized component, and the assembly nobody owns. Components get recognized; end products get listed. Those are different records, and only the second one covers the box you actually buy. ## Verify Before You Pay, Write It Into the PO Ask for the file or control number of the exact model, then look it up in the certifier's own public directory. UL Solutions and Intertek both publish lookup tools. A screenshot from the seller proves the seller has a browser. Match three things: the listed company name, the factory location, the model description. Then put the listed model and the mark requirement into the purchase order, and have the pre-shipment inspector confirm the label on the finished goods. That sentence in the PO is what turns a nice brochure into an enforceable requirement. On the physical side, the numbers that matter: SPT-2 18/2 cord, 8A and about 960W for a 250ft run; C7 bulbs on E12 candelabra bases, C9 on E17 intermediate; LED white binning pinned to Kelvin against a kept sample, because two "warm white" batches from different bins read differently on the same roofline. CPSC treats minimum wire size and strain relief on decorative lighting as substantial hazards, and the importer owns that product once it clears. If a venue, a property manager or an insurer asks whether your christmas string lights are listed, the answer should be a file number you can read out loud. ## Frequently Asked Questions **Is ETL as good as UL for christmas string lights?** Both are OSHA-recognized NRTL marks and can certify to the same US safety standard, ANSI/UL 588. What matters is that the exact product is listed and the record checks out in the certifier's directory, not which logo is on the box. **How do I check whether a factory's UL or ETL listing is real?** Ask for the file or control number of the exact model, search it in the certifier's own public directory, and confirm the company name, factory location and model description all match your order. **What cord and bulb specs should I pin in the PO for led christmas lights?** SPT-2 parallel cord with gauge printed on the jacket (18/2, 8A, around 960W for long runs), E12 candelabra bases for C7 and E17 for C9, socket gaskets present, strain relief at the plug, and LED color temperature in Kelvin matched against a retained sample. See our 300LED connectable icicle christmas string lights, the 100LED warm white icicle string, and the 100LED copper wire fairy lights.