Inside has been in development at Playdead for five years — Limbo debuted in July 2010 on Xbox 360.
"After 5 years in development, we, more than anyone, are looking forward to the release," said Playdead in a press release. "We are so close, but getting it right has taken a little more time than we anticipated."
Playdead gave no new release window alongside the delay announcement, saying, "When we know more about the release timing, we will let you know."
The studio hasn't said much about Inside beyond its announcement at E3 2014 with a trailer. The E3 trailer, which you can watch below, features a boy making his way through drab environments in side-scrolling platforming. Inside will debut on Xbox One.