Sensabaugh started all 16 games at strong safety for the Cowboys last season, finishing tied for the team lead with five interceptions and tying for third with nine pass breakups.
"Headed back to the Big D.," Sensabaugh posted Tuesday evening on Twitter.
He followed up Wednesday morning that he had landed in San Antonio and was headed to the Cowboys' practice facility at the Alamodome.
For the third straight year Sensabaugh does not have a long-term deal. In 2009 he joined the Cowboys from Jacksonville with a one-year, $1.75 million deal and was given a second-round tender offer of $1.82 million last year as a restricted free agent.
He said the Cowboys and some other teams offered multiyear contracts but they were not enough to get him to sign.
"I decided to chance it on a one-year deal again and hopefully it works out for the best," Sensabaugh said. "I'm going to go out and play my heart out."
Cowboys executive vice president Stephen Jones had said on Monday the team was looking to address the safety position and could add two.
The Cowboys have also expressed interest in Abram Elam, who played for the Cleveland Browns the last two seasons, because of his knowledge of defensive coordinator Rob Ryan's 3-4 scheme. But the team has yet to work out a deal with Elam.
Sensabaugh struggled at times last season, his second with the Cowboys, but improved as the year progressed. He wanted to return to the Cowboys, but not before seeing what the free agent market looked like.
The Cowboys also signed defensive end Jason Hatcher on Wednesday.
Calvin Watkins covers the Cowboys for ESPNDallas.com. Information from ESPNDallas.com's Todd Archer was used in this report.