Do QR codes expire?
A QR code itself cannot expire. What can stop working is the link inside it, and that depends on the kind of code and the service that made it.
Static codes never expire
A static code holds its content directly, so it will scan for as long as the print lasts. The only way it "breaks" is if the page it links to is taken down or moved.
Dynamic codes last as long as the service keeps them on
A dynamic code holds a short link that belongs to a QR service. If the service switches that link off, every printed copy stops working at once. Many generators offer dynamic codes free only for a trial and deactivate them when the trial ends, which is the most common reason people find their printed codes suddenly dead.
Read the plan terms before you print. Look for what happens when a trial ends, when you cancel, and when you go over a scan limit.
How QRGlo handles it
Codes made here never stop redirecting because of your plan. There is no trial and no scan limit. A free account includes 3 editable codes; if you cancel Pro, codes beyond those three become read-only but keep working.
You can still set an expiry yourself: give a code an end date or a maximum number of scans, and send later visitors to a page of your choice.