The midfielder has been on trial at Hereford FC throughout pre-season after previously playing for fellow National League North outfit, AFC Telford.
Speaking to the OS, McQuilkin said: "I’m really happy to be back at this club, I’ve got a lot of good memories here and I’m looking forward to getting going.
“I’ve had a good pre-season and settled in well with the lads, it’s been nice to be kicking a ball again and I’m really looking forward to getting going on Saturday.”
Hereford manager Josh Gowling added that, during pre-season, McQuilkin has been really comfortable on the ball, good in possession and can play in a couple of positions which is really good.
McQuilkin, who is now 31, played 76 times for Hereford between 2009 and 2013 before joining Kidderminster on loan. He later joined Kidderminster for a second time after spells at Walsall, Hednesford, Torquay and Telford, He signed for Telford for a second time in 2018, scoring one goal in 26 games.