Widdop will now remain at the Red V until the end of the 2021 NRL Telstra Premiership season.
The England international has been an integral member of the Dragons since his arrival in 2014, where he became sole captain of the club this season.
Widdop has played 79 games for the Dragons to date, and on Anzac Day against the Sydney Roosters will play his 150th NRL game.
Widdop also recently became the second-highest pointscorer in St George Illawarra history and is now on track to surpass Jamie Soward’s record of 977 points.
The 28-year-old was pleased to remain at the Dragons for the next four years.
“The Dragons have grown more and more since I’ve arrived. There’s a good environment here and it’s a good place to be so I wanted to play my part in that,” Widdop said.
“At this stage of my career it certainly was a big decision for my family. I have three young kids, I’m very settled here in Wollongong and I’m enjoying my time here.
“So while it was a big decision, I’m happy to be staying.”
Dragons Director of Rugby League Pathways Ian Millward explained the reasoning behind Widdop’s deal.
“We have shown a lot of confidence in Gareth as our long-term leader by offering him a four-year contract,” Millward said.
“We were very conscious of creating stability and consistency in our team and we feel we have achieved that with the re-signing of Gareth.
“Gareth’s our leader and obviously plays in a vital position so we’re over the moon that he has re-signed.”
This was first published on the St George-Illawarra Dragons website