The 23-year-old Swans defender, who will be out of contract at the Liberty Stadium at the end of this season, is expected to complete a season long loan deal with The Seagulls on Wednesday.
"I'm looking forward to the challenge at Brighton," Painter told the official Brighton website.
"I've spoken to Gus Poyet and I think he's looking at me as a centre-half as well.
"They need to get away from the bottom end of the table, but they've got a few games in hand and I'm committed to helping them climb the league.
"I'm fully committed to the challenge and I really want to do a good job there.
"The last time I played at Brighton was when Swansea lifted the League One trophy in 2008 so that must be a good omen!"