Said Sensabaugh in a tweet: "Been informed I'm being released for cap purposes... had a great run #CowboysNation I appreciate the organization and my teammates."
The move saves the Cowboys $1.4 million in salary-cap space. Sensabaugh's $3 million base salary would have been guaranteed had he been on the roster March 12.
Sensabaugh joined the Cowboys in 2009 after a four-year run with the Jacksonville Jaguars and played on three straight one-year deals before signing a five-year extension with the Cowboys in December 2011.
He started all but two games in which he played for the Cowboys and had eight interceptions, none last season. He finished the 2012 season with 62 tackles and forced a fumble.
The move leaves the Cowboys with a glaring hole at safety. Barry Church is recovering from a torn Achilles, and the team doesn't have another player under contract who has started at the position. Matt Johnson missed his rookie season with hamstring injuries. Danny McCray (restricted), Charlie Peprah and Eric Frampton started games in 2012 but are free agents.