The 25-year-old – who made his international debut earlier this year – has put pen to paper to join the Men of Gwent from English Premiership side Saracens.
Dean Ryan, Director of Dragons Rugby, said: “We’re delighted to be able to welcome a player of Nick’s calibre to the region.
“He has enjoyed success in a Saracens shirt and he brings that winning mentality and attitude, as well as enjoying a fresh environment and competition in which to challenge himself.
“Nick’s experience will undoubtedly bring out the best in those around him in our squad and we know he will leave an indelible mark on his time at Rodney Parade.”
Capped by Wales in all four games during the 2020 Guinness Six Nations, Tompkins scored a try on his debut against Italy at Principality Stadium in the opening round of matches.
Tompkins has won four English Premiership titles and three European Champions Cup titles during his career with Saracens.
Tompkins said: “I am really looking forward to joining the Dragons.
“The region is clearly making great progress, under the guidance of Dean Ryan, and I am really excited about contributing to the cause.”
One his loan period is concluded, Tompkins will return to Saracens.
His affiliation with Sarries dates all the way back to 2008 when he would attend rugby camps held by the club before he joined the Academy in 2012.
He made his debut for the Men in Black that same year in the LV= Cup against Leicester Tigers and a Premiership debut followed in 2014 against the same opposition.
Tompkins played in every single Premiership fixture in the 2018/19 season, contributing 11 tries in what was a tremendous defence of the title.
And he also proved just as important in Europe that season, scoring key tries against Lyon and Glasgow Warriors as Sarries went on to earn a third Champions Cup triumph.
His excellent form in the first half of the 2019/20 season earned Tompkins an international call-up with Wales for the 2020 Six Nations, during which he scored his first try on debut.
Saracens Director of Rugby Mark McCall said: “As a youngster in our Academy it was clear that Nick was a player of real potential and we have enjoyed watching him grow and develop both on the field and as a young man.
“As a club we are delighted that Nick has chosen to continue to realise his potential with Saracens.”
