The first question is whether the veneer is a color match to the adjacent teeth. No restoration changes color with any type of bleaching. If the veneer matches now, it may not match after bleaching the other teeth. If the veneer is lighter than the natural teeth, then you may be able to improve the color match by bleaching the natural teeth to match the veneer. However, I would do that slowly with daytime wear of the tray technique using 10% carbamide peroxide. Interestingly enough, with a veneer, you can bleach the tooth underneath the veneer, and sometimes the veneer looks lighter after bleaching, depending on the veneer’s translucency. If the veneer matches, or is slightly darker than the other teeth, I would try bleaching the veneer tooth substructure first with a single tooth-bleaching tray that only applies tray bleaching to the veneered tooth. In-office whitening is not an option because of the application time and control, as this process sometimes take 8 weeks of nightly tray bleaching using 10% carbamide peroxide (which would possibly be about four or more in-office treatments). You can find the pictures of the single tooth tray design on my website www.vanhaywood.com in the articles section. Look for the article on single dark teeth. Once the veneered tooth has reached its maximum lightening and you have waited 2 weeks for shade stabilization, then you can use a full tray in the day wear to titrate the natural teeth to that veneer color. If you just bleach all the teeth including the veneered tooth with in-office or full tray, you run the risk of having the patient look worse because they now have a single dark tooth rather than a uniform smile.