Belfast-born Kearns, 20, started his career at West Ham before moving to Dundalk in August 2010 following his release at Upton Park.
A statement on Dundalk's official website confirmed a deal had been agreed, adding the youngster will travel to London Road on Monday for a medical and to complete paperwork.
Kearns himself told Dundalk's website: "I'm delighted with it.
"It's a massive step for me. It's a massive opportunity and I'm really looking forward to it. And obviously I'm really looking forward to, hopefully, playing under Darren Ferguson, going in and getting a chance and showing him what I'm about."