A critic for The Daily Telegraph summarised the series as "a triumph against TV's ageism", and it has been endorsed by an executive member of the charity Age UK.

[6] Alan and Celia's romance is depicted alongside the troubles of their own grown daughters, and the series' official description says that its portrayal of family is "as dark as it is comic".

Wainwright felt that killing off Caroline's partner, Kate, would be the most effective way to propel the drama onwards and to develop the emotional lives of the remaining characters - however 'killing the lesbian' is a well-known homophobic film trope.

[18] Reid identified herself with Celia's personality – believing herself to be quite reckless and outgoing –[15] though stated that unlike her character she has no desire to enter another relationship.

[7] She stated the series' ensemble cast was "the closest I’ve come to being in a theatre company on television" due to how well the actors worked together.

She admired the character's honesty, bravery and lack of self-pity and identified strongly with her tendency to speak before thinking things through and her deep love for her father.

[22] She felt the series showed a very adult approach to storytelling, stating that she had "never come across a character like Gillian before" and praising the variety of strong female roles.

Timothy West appears as Alan's brother, Ted, whilst Gemma Jones plays Celia's sister, Muriel.

[28][29] The third series later introduces Rupert Graves as Gary, who is revealed to be Alan's illegitimate son,[30] and Michelle Hurst as Kate's mother, Ginika.

Jane Shilling of The Daily Telegraph labelled the series "a triumph against TV's ageism" in an examination of the portrayal of elderly people in the media.

[71] Shilling singled out Jacobi and Reid's performances, stating that they provide a "mixture of gravity and levity" that "brings a transcendent quality to their characters' resolute ordinariness".

Lucy Harmer, an executive member of the charity Age UK, also praised the series for portraying two "normal, healthy and sane" older characters, citing the depiction of Internet use by the elderly as something ordinary.

She compared the treatment of older characters in the series to Hilary Boyd's novel Thursdays in the Park and the film The Best Exotic Marigold Hotel (2012).

She wrote the story was poignant and praised a central theme underlining "how many people make do with their day-to-day business and responsibilities, while still holding on to their private dreams".

[73] Andrew Anthony of The Guardian had his "low expectations ... squarely confounded", giving particular praise to the dialogue and the central performances.

She also praised Wainwright's script and the lead quartet of Jacobi, Reid, Lancashire, and Walker for creating "characters you can believe in even when they're behaving appallingly".

[74] The series was reviewed favourably by the American website AfterEllen, which reports on the depiction of gay and bisexual women in the media.

Mary McNamara of the Los Angeles Times labelled the series as "the best new show of the fall", describing it as "a rapturous mix of absurdly fairy-tale-romance and frantic modern complications, set in the picturesque drear of Yorkshire and brought to life by masterfully shaded performances."

[76] Matthew Gilbert of The Boston Globe acknowledged that the US public might not find the series appealing based on its title and premise alone, stating that PBS' description of the programme made it sound "as saccharine and hackneyed as a Geritol commercial".

However, he felt that series also distinguished itself from this category of media by its "relatively dry style and careful modulation of tone and volume" in addition to "a crackerjack cast".

[79] Additionally, Wainwright was named best Drama Writer at the 2013 British Academy Television Craft Awards for her writing of the series.

[81] In 2014, Sarah Lancashire and Nicola Walker were both nominated for a British Academy Television Award in the category for "Best Supporting Actress" for their roles in Last Tango in Halifax.

[83] Sally Wainwright mentioned this development at a Broadcasting Press Guild event and stated that, though she did not expect to be closely involved in the remake, she would have an associate producer role.

[83] However, the following day Red Production Company released a statement stating that a remake would probably be delayed since the original series was still airing on American channel PBS.

[84] In April 2014, it was reported that the series would be remade for French television by BBC Worldwide France and the production company NEWEN.