Every code on Promio carries a verification state and the date it was last checked. This page explains exactly what those mean, so you can judge how much weight to put on them.
What "Verified" means
A Verified badge means someone loaded a real cart at that retailer, applied the code, and saw the discount line appear in the order summary. It does not mean the code will work on your cart — exclusions still apply, and a code that works on one basket can be rejected on another.
What an unbadged code means
No badge means the code came from a credible source and has not been rejected, but it has not been tested against a cart in the current window. These are worth trying; they are simply less certain.
The check date
The date shown on each offer is the last time the code was tested, not the date it was added. An old date is a real signal: try the next code in the list first.
Deals versus codes
Offers marked Deal have no code. The discount is applied to the product or attached to the browsing session, so it cannot be pasted anywhere. These fail far less often than codes, because there is nothing for checkout to reject.
When a code stops working
Tell us. Codes are rechecked on reader reports before anything else, and an offer that fails verification is unpublished rather than left to waste your time.