The 18-year-old started out with Sunderland before joining the under-23’s set-up at St Andrew’s.
The 6ft4ins shot-stopper went straight into the squad for the Pitmen’s trip to Nuneaton Borough today.
Basey said: “I’m excited to get going for the Pitmen. I have so much to offer, and I hope to make the fans proud.
“I’m here to win games and truly showcase everything I’m capable of.”
Pitmen boss Keenen Meakin-Richards said: “Oliver is a tall and imposing keeper and athletic shot-stopper.
“He has played at levels already which only the best is good enough, or you get cut adrift.
“Oliver has showed his continued improvement and his worth to big clubs, which secured his pro contract.
“He has also shown to us, he will assist us in pushing forwards and adding more strength and depth to our rear guard action. We’re excited to have him on board.”
Basey has made four appearances for Blues’ under-23s so far this season.