The London club confirmed that they had allowed the player to leave the St. Albans based team where he has played his rugby at Saracens since 2008.
The 6'7", 18-stone Hayden, was born in Australia but played college basketball at Metropolitan State in Denver, and started all four group matches for the USA at the 2011 Rugby World Cup.
“Playing in the NFL has been something I've always wanted to do and it’s been a dream of mine,” Hayden told Saracens' website.
“After the Rugby World Cup it became clear that this dream might become a reality, and in February things started to become more serious.
“I travelled to the US to train with a number of teams and ended up having a few options. I've settled on New York and feel that the Jets are the best fit for me.
“Saracens has been an amazing part of my life and I feel fortunate to have been here. The club has been fantastic in allowing me to pursue my dream and I will always be thankful to them for that. While I'm very excited about what lies ahead, it’s with a great deal of sadness that I am leaving the Saracens family and being part of the club day-to-day.
“It’s been an incredible journey and I feel very fortunate that I've managed to make the most the opportunities that have come up for me.
“I know the story is not complete though and realise there's a lot of work I need to do to make this next phase of my career a success.”
The New York Jets hope to develop Hayden as a Tight End – a hybrid offensive position that encompasses both blocking and catching balls like a wide receiver.
"Without a doubt there is a lot of work I need to do to play at the highest level," he said.
"I'd be doing the players in the NFL a disservice if I thought I could contribute straight away. I'm not afraid of putting in the hard work though and with a bit of luck, hopefully, I can contribute and be a good player.”
Punter Ben Graham, a former Australian Rules footballer, also played for the Jets from 2005-07.