Critical response
The film was initially broadcast in the United Kingdom on BBC Two on 17 June 2021. On the review aggregator website Rotten Tomatoes, 70% of 76 critics' reviews are positive, with an average rating of 7.1/10. The website's critics consensus reads: "Together is a little too effective at recreating the lockdown experience, although Sharon Horgan and James McAvoy are an appealing duo." On Metacritic, the film has a weighted average score of 57 out of 100 based on 15 critics, indicating "mixed or average reviews".
From The Guardian, Lucy Mangan gave it four stars out of five, writing that while not everyone would enjoy it, Together presented a "miraculous compression" of 2020. In her review, Mangan mentioned her belief that the film was the first to succeed in projecting an honest experience from the living during the COVID-19 pandemic. Furthermore, she described it as a "claustrophobic" viewing, detailing the usage of monologues to dispense information and how it "captures perfectly the emotional dilapidations of a dying relationship".
Writing for The Irish Times, Ed Power gave positive remarks to Sharon Horgan's performance but found the fourth wall breaks "discommoding" to the viewer. In their final comments, Power wrote that the finale was "a vaguely happy conclusion – but, more importantly, an honest one". Meanwhile, Radio Times's Flora Carr described the film as "savagely funny" and "completely devastating". Comparing it to Staged, Carr lauded Together for being able to address serious issues related to the COVID-19 pandemic in a "brave and brilliant" manner. Similarly, Emily Maddick from Glamour summarized the film by writing that it would "leave you laughing, sobbing and furious". On the fourth wall breaks, Maddick wrote that they would "[make] the viewer feel like they are the mediator in the heated venom-filled arguments as opposed to flies on the wall."
Rachel Cooke, writing for New Statesman, gave a negative review and found it was a "cheap and obvious pandemic piggybacking" film she described as "tedious and excruciating". Writing for The Independent, Ed Cumming gave it four stars out of five, describing it as an "unflinching domestic lockdown drama". Additionally, Cumming wrote that "sometimes Together is very funny. I expect many viewers will relate to its vision of the realities of life in lockdown. Its depiction of the gap between the irrepressible people we heard about, who spent the time taking up new hobbies, and the rest of us, who were just trying to limp across each day, is spot on." On the major theme of the film, he found that it was about responding to new struggles: "When it comes to the past 18 months, the right response has rarely been clear."