The 31-year-old has been training with the club's Under-23s for the last number of weeks after leaving Australian side Melbourne Victory.
Butterfield made 100 appearances for the Reds after making his professional debut with the club in 2007. He joined Norwich City in 2012 before joining Middlesbrough in 2013.
The Bradford-born midfielder moved to closer to home in 2014 as he signed for Huddersfield Town. He would go on to be named Supporters' Player of the Year by the Terriers faithful during the 2014-15 campaign.
A move to Derby County followed his departure from Huddersfield. It was at the Rams he had loan spells at Sheffield Wednesday and Bradford City.
However, he is now without a club after leaving Melbourne and although he is not on trial with the Tykes, he would certainly be open to joining them again permanently.
He told the Barnsley Chronicle: “I haven’t had any calls for Barnsley about a contract, but my phone is on. I would be open to it but it’s up to them.
“I love Barnsley. They gave me my breakthrough in the game. If I ever got the chance to play for them again, I would love it. If it’s not as a player, then maybe in the future as a coach.
"That’s something I would like to go into in a few years when my playing career finishes.
“I am just here to get fit with the 23s. Whatever happens, it’s been great to be back for a few weeks at a club I love.”