As part of its stunt, the network will carry the wedding on a Clear Channel digital billboard as well as its pre-show, beginning on the Times Square screen as early as 4:30 a.m.
It is also using the outdoor-cast as part of a broader stunt that involves a fashion show linked with its "Say Yes to the Dress" show. It is holding the on-site marriage of three couples, and offering a performance by pop singer Colbie Caillat.
The Clear Channel billboard is visible from the new red steps that serve as a resting place behind TKTS in the heart of Times Square.
Onlookers, however, may be able to choose from other screens in the Square to watch the ceremony as coverage from ABC and Fox News -- maybe even MSNBC --could also be available.
The Weather Channel recently launched a new series with a live simulcast on a Times Square billboard.
This week, TLC is airing wedding programming that includes an exploration of how Prince William and his bride-to-be reached this point, a look at William's brother Harry, and a recounting of what it was like to be a bridesmaid for Princess Diana years ago.
While the Royal Wedding may be a brand, TLC faces competition from numerous networks in pre-event coverage and could suffer from any viewer fatigue.