Tyler Garratt, a 23-year-old left-back, is the sixth signing for Wrexham manager Dean Keates in 2020.
The Dragons still had the option of loan signings even though the transfer window has closed and Garratt joined Wrexham from Stockport County.
He has committed to the end of this season, covering the loss of James Jennings to injury.
Lincoln-born former Bolton Wanderers defender Garratt follows Davis Keillor-Dunn, Dan Jarvis, Jordan Ponticelli, Jay Harris and Jordon Thompson to the Vanarama National League club.
“It all happened quickly,” said Garratt. “I was training at Stockport when an agent called me with the news.
“I’ll be working to get forward and get crosses in. I’m reasonably quick and work hard defensively as well.
“My aim is to play as many games and provide as many assists as possible.”
Garratt, who came through the youth ranks at Lincoln City, could make his Wrexham debut at Chesterfield this afternoon.
He has experience of Championship football (Bolton Wanderers), League One (AFC Wimbledon) and Doncaster Rovers (League Two) plus National League with Eastleigh and Stockport.