"The End of All Things" first aired on February 24, 2012 in the United States. The last episode before a four-week hiatus, it was watched by an estimated 3.1 million viewers, with a ratings share of 1.2, an improvement from the previous episode, "". and its lead-in helped its network, , tie for third place with for the night.
Writing for , columnist Noel Murray graded the episode with an A-, and praised September's stumbling entrance into the lab as "yet another rich and remarkable scene". writer Jeff Jensen had a more negative opinion, and commented that the episode "failed to make my dinger hum," which he attributed to high expectations set by fellow staff writer and former reviewer Ken Tucker. Jensen continued, "It was, to my eyes, 'just okay.' Certainly not the equal of the past two episodes. And not the strongest possible kicker to a strong second act for s fourth season, which now takes a four-week snooze before rising anew on March 23 for the first of eight consecutive episodes – a sweep of story that might represent the very end of all things . Damn, I’m such a downer this week, aren’t I? Ah, but so was this episode." In January 2013, IGN ranked the episode as the fourth best episode of the series, explaining that "when Season 4 needed a boost of excitement, this episode delivered it in a timely fashion. It had a thrilling pace and offered answers to some questions that have lingering since the series began."
Lieutenant Wilson and Colonial Union diplomats must race to keep the peace, seek reconciliation with an enraged Earth, and maintain humanity's unity at all costs. If they don't, it will mean oblivion, extinction and the end of all things.