Everington joins the Reds until the end of the season and comes straight into the squad for our trip to Spennymoor Town today.
Everington came through the youth ranks at Lincoln City and made twenty-one appearances during the 2015/16 National League campaign.
Last season he was loaned to Buxton on a one-month loan deal but rarely featured for the Imps during last season and was released at the end of the 2016/17 campaign.
He then joined Grantham in July and has made ten appearances for the Gingerbreads this season.
Reds boss John McDermott told his club`s website: "Kegan is a very athletic lad, he gets about the pitch well and he likes to get on the ball and move it. He's a good passer, the key element for me was to get Kegan involved in the attacking side more, I want him to join in and score goals.
"He's a similar player to Tom Platt and it`s an area we've needed to strengthen in. We now have another option in midfield. He will bring quality, strength and size and will be another threat for us at set pieces.
"We've beaten other clubs to his signature and we are delighted to have him here at the Reds."