The shotstopper arrives at the Sands Venue Stadium for his first EFL loan spell away from the Sky Blues.
Billson has risen through the ranks in the youth set-up at Coventry, making a breakthrough in the Under-23s during the 2018/19 season, where he also went out on loan to non-league side Barwell towards the end of the year.
He enjoyed a run in the Under-23s during the 2019-20 campaign, as he established himself as number one. The youngster’s performances throughout that year saw him rewarded with him making his professional debut for City in the Carabao Cup second round against Gillingham.
Another impressive season with the Under-23s saw Billson rewarded with a new contract back in December of 2020, as he extended his stay with the Sky Blues until June 2023.
First team manager Neil Cox told iFollow Iron: "This is one we've been trying to sort for five or six weeks now. I'd just like to thank Coventry City for helping us out and making this happen really.
"The boy's been excited about the prospect of coming to this football club but everything had to be done right, and I'm over the moon that he's in the building.
"He's 6ft 3in, a big unit, strong, brave and got a lot about him. He's an organiser and another good player we've brought in. I think he'll be a good signing for us.
"(Coventry manager) Mark Robins rates him highly and he was telling me how he's an excellent goalkeeper, a brilliant shotstopper and has been in and around their first team but he needs a loan move.
"He's been training with Coventry so far this pre-season and now comes into the building, and has enough time to play some friendly games with us."
The transfer is subject to EFL ratification.