Is there any way I can tell server side if the user is blocking my cookies?
Other than by their absence, nope. It would require two requests from the server in controlled order. But you can detect it from javascript rather easily which might help you. var randstuff = Math.random().toString().substring(2); document.cookie = "randstuff="+randstuff; var accepts_cookies = (document.cookie.indexOf(randstuff)!=-1); document.cookie = "randstuff=0; expires=Tue, 1-Jan-1980 02:02:02 GMT"; There is other code out there that assumes if document.cookie contains data that cookies are accepted. I learned that with Moz 1.1 this is not true. You need to perform an actual set-check test. You could (this is gettin' scary here) then use more Javascript to modify all links on a page to add whatever state data you desire. This is actually pretty easy (see document.links) unless you've got frames in which case it is only slightly challenging. But as we all know, the Javascript road is paved with pain and suffering for nothing more than pretty baubles.