The 40th Annual CMA Awards will air Nov. 6 on ABC.
Urban is nominated in the two categories he won last year: entertainer of the year and best male vocalist. He's also up for best single, "Better Life," and song of the year, for co-writing "Tonight I Wanna Cry."
The Grammy-winning country singer released a statement Friday that said he entered rehab Thursday night with his wife, Nicole Kidman, by his side. His publicist would not give the location of the rehab center.
Urban, who turns 39 on Thursday, has publicly acknowledged a previous addiction to cocaine.
"One can never let one's guard down on recovery, and I'm afraid that I have," the statement read.
Urban's new CD, "Love, Pain & the whole crazy thing," will be released Nov. 7 as scheduled, but he will postpone all upcoming promotional appearances.