Burleson tweeted Saturday morning: "It is official so 'Go Lions.' "
In going to Detroit, Burleson will reunite with offensive coordinator Scott Linehan. Under Linehan, Burleson had his best season in 2004 when he caught 68 passes for 1,006 yards.
According to the source, Burleson will receive $11 million in guarantees.
Burleson, 28, was considered one of the top receivers in free agency. He had been with the Seahawks the past four seasons. His contract voided this year, making him an unconditional free agent.
The Lions will count on him to complement receiver Calvin Johnson and perhaps give their special teams a reliable returner.
John Clayton covers the NFL for ESPN.com. Information from The Associated Press was used in this report.