Several critics of the
Octopus album, singled out "Tell Me When" as a standout track.
Dave Thompson of
AllMusic said it echoes earlier material, likening it to "
Fascination" and "
Mirror Man". He went further, saying that "the real difference is found in the vignette-esque lyrics and the more complex vocals. And these slight changes make all the difference, turning synth dreams into
techno club success." David Bauder of
Associated Press called the song "splendid", and noted that it is a "shimmering melody, with
Kraftwerk-like synthesizers and Phil Oakey's arch voice sweetened by his two female colleagues. It ranks with their best work." He added that it was the only song from the album "with any worth". Also
Larry Flick from
Billboard magazine was favourable, writing, "British synth-pop act that enjoyed a high profile during the '80s returns with a percolating swinger, which harkens back to its now-classic hits, '
Don't You Want Me' and 'Fascination'." He also named it a "
disco-hooked number". Anderson Jones from
Entertainment Weekly described it as "bubbly" and "radio-friendly", whilst calling the album "lackluster". In his weekly UK chart commentary,
James Masterton said, "It may not be the biggest new hit of the week but it is certainly the most significant", concluding with that it is "sounding like typical Human League of old". Jennifer Nine from
Melody Maker viewed it as "a brightly hopeful, wafer-thin compendium of standard League traits, including that pocket calculator-powered "funky" breakdown." A reviewer from
Music & Media commented, "Comeback of the year? That's up to you. Anyway, the return of the
Sheffield synth band in the premier division of pop creates an enormous buzz in radio land." In the album review, the reviewer said that "Tell Me When" "portrays Phil Oakey and the girls as a perfect replica of the electro pop band around 1981's
Dare album."
Music Week gave the single a top score of five out of five, describing it as "pristine synth pop as a deep Oakey lead and girl harmonies make this the most joyful single of the week. Welcome back." John Kilgo from
The Network Forty wrote, "This is a great comeback for the Sheffield, England trio! A
techno-pop release full of energy highlighted by a very catchy hook. This smash is a no-brainer." Another
NME editor, Paul Moody, viewed it as "sublimely clumsy" with "this killer Human League chorus all over it, the sort that rings around your brain like a nursery rhyme from
Mars."
People Magazine stated that "their hot new single 'Tell Me When' has made the Human League hip again". They added, "But the tune is an infectious anachronism—the synthesizer trio still tinkle about as soullessly as they did in 1982, when they hit No. 1 with 'Don't You Want Me'."
James Hamilton from the
Record Mirror Dance Update named it "typical Human League holler" in his weekly dance column. Tony Cross from
Smash Hits felt it's "the best thing" on the album. David Sinclair of
The Times commented, "All the familiar components are here join-the-dots tune, danceable synth-pop arrangement, catchy bubblegum
chorus but the result sounds disconcertingly like the Human League by numbers." ==Music video==