Routt signed to a three-year, $11 million contract with $6.5 million guaranteed. He made $10 million last year with Oakland.
"Stanford has a proven record of success in the NFL," said Chiefs coach Romeo Crennel. "He's a talented player that has spent seven seasons in the AFC West, so he is familiar with us and our division opponents."
The Tennessee Titans and Minnesota Vikings also expressed interest in Routt, but it was too late. Routt was scheduled to make $5 million had he stayed with the Raiders. Routt also had 49 tackles last year as well.
With this signing now, Kansas City's cornerback troubles are fixed with him and Brandon Flowers making a solid one-two punch in the secondary. However, this also means that they will most likely not be able to re-sign Brandon Carr.
The 28-year-old Routt is looking to make a lot of impact for a young, bright squad as he enters his eighth season.