The defender underwent surgery to repair a ruptured cruciate knee ligament in April last year, keeping him out of the first team until last week.
Hamill played the last half-hour of the 2-0 defeat to Aberdeen at the weekend, and he got more game time under his belt with an appearance for the U20s in Tuesday's 2-2 draw with Edinburgh rivals Hibernian.
Hearts coach Darren Murray is confident Hamill will be involved in Saturday's SPL encounter against Ross County at Tynecastle, although the club are being cautious not to rush his return.
"Jamie done OK and there has been no reaction from his knee, so hopefully he will be back training with the first-team on Thursday" Murray said.
"We'll then have a look and see how he is and hopefully, everything going well, he'll definitely be involved in the squad on Saturday."