Addai began his career at the Arsenal youth academy before linking up with the Coventry U18 team in 2014. Whilst with the Sky Blues, Addai enjoyed loan spells with Mickleover and Telford United.
The young shot-stopper has trained with the Reds for the last week and featured as a trialist in Crawley’s pre-season opener against Eastbourne at the weekend, keeping a clean sheet in the process.
Since then, Addai has flown out to Murcia to join the lads in Pinatar for a six-day warm-weather training camp.
Addai said: “It feels very good to get the deal done. I think that this is a very good club to be at. I have been here for over a week now, and I have really enjoyed my time, so it made sense for me to get the deal over the line.
"When Crawley came up, I knew it was the perfect option for me. Being a young pro, I am very happy to be here at a club like Crawley.
Manager Kevin Betsy said: “We have been really impressed with Corey during his time with us. He has trained really well and adapted to the style of play that we are looking to implement, but most importantly, he is a great shot-stopper. He is really good inside the box and has a fantastic presence.
"Corey will provide very strong competition to Glenn, who has been a fantastic servant to the club. It is very important to have good competition from a younger goalkeeper. We are delighted that he has chosen to join us.”
See more Crawley Town news here.