The academy graduate made his debut for the O’s in 2017 and has since made 140 appearances in an Orient shirt.
Happe played 40 league games in the 2020/21 campaign, netting on three occasions, including winners against Grimsby Town and Bradford City.
“I’m happy to get it over the line finally, and I’m really excited to get started next week with pre-season,” said Happe, after penning his new contract.
“There’s a good group of players around me, a lot of experience in this league and the league above, so it’s a great opportunity for me to keep learning.”
“I thought I started off last season well, but probably let myself down towards the end of the season – so I’m excited to get back to it and prove the doubters wrong.”
Happe is the second O’s player to agree a new deal, following midfielder Craig Clay. Last week, the O’s confirmed Omar Beckles and Connor Wood had signed for the Club, bolstering Orient’s defensive options.
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