One More Day received an overwhelmingly negative reaction from fans and critics. IGN reviewer Jesse Schedeen described Amazing Spider-Man #545 as "undoubtedly the worst comic Marvel published in 2007" and a "deus ex machina of the highest order." He did admit that writer Straczynski "had a great handle on the Peter/Mary Jane dynamic," making their potentially final moments mean something, and that Quesada's artistic style made sense given the dark tone. However, he also dismissed the story as "infuriating and downright disrespectful to anyone who has come to love Spider-Man comics over the years." IGN published two "Additional Take" reviews for Amazing Spider-Man #545. Bryan Joel said that he'd been a "vocal supporter" of "Brand New Day", but summarized the OMD story as "flip, weightless, and painfully brief." Richard George stated that "One More Day" "could prove to be the best example of editorial influence gone horribly, horribly wrong" and "in trying to preserve the appeal of Peter Parker, Joe Quesada has actually managed to fundamentally undermine the character." Both Joel and George agreed with their colleague in complimenting Quesada's artwork.
Spider-Man creator Stan Lee praised the storyline and what he perceived as the courage its writers and creators showed in so drastically changing a popular and well-established character. Lee said changes are needed to keep a series fresh and compared the criticism from fans to the backlash Marvel Comics received when Peter Parker and Mary Jane Watson married in the first place. However, in the newspaper strip he pens, he wrote a deliberate parody of the "One More Day" retcon, revealing that it was in fact a bad dream. Peter remains married to Mary Jane in the newspaper strip.
In a roundtable review at Newsarama, J. Caleb Mozzocco agreed that Spider-Man was easier to relate to while young and single, but that retconning the marriage of Spider-Man was unnecessary due to the existence of titles such as Ultimate Spider-Man and Marvel Adventures Spider-Man. He found the story confusing, wondering how this retcon made sense in the larger Marvel Universe as Spider-Man played important roles in New Avengers and Civil War. Kevin Huxford claimed, "you can feel editorial mandate dripping from this" and called the story "utterly ridiculous," while Lucas Siegel criticized Quesada's decision to have heroic Peter Parker make a "deal with the Devil" for selfish reasons. Richard Renteria felt that the story's conclusion was a missed opportunity "to add a new layer of guilt to Peter’s already rocky life by allowing May to finally have the send off she deserves," while Troy Brownfield felt that the storyline damaged Marvel continuity and Spider-Man's decision was "selfish and childish," not to mention "a big middle finger to the idea of marriage in comics." He speculated preferable endings to the story before concluding, "As it stands, Peter, MJ, May . . . and the readers . . . all got a raw deal." A more positive view came from Brandon Thomas, who felt that "One More Day" was "an incredibly well-told story." He praised the writing, in particular the morally ambiguous decision Peter has to make and the way he and Mary Jane deal with it together, as well as Quesada's art, which he felt set the tone of "guilt, regret, and despair." In regards to the change made in Spider-Man canon, he said, "Peter Parker being married really isn’t a vital component of the mythos" and that it allowed Marvel to make "big, sweeping changes to bring things slightly more into focus and back on message."
Joe Quesada, co-writer and penciller. Wizard felt his artistic decisions enhanced the series.
Wizard praised the artwork, specifically the way Quesada differentiated visually between the dark and light tones before and after the retcon. However, they felt "the entire set up and execution just doesn’t make sense" and failed to empathize with the characters and their decisions. They criticized the use of magic in a largely science-based book, calling it "the biggest cheat since Dallas." They also felt that the concept of making Spider-Man more accessible was undermined by the new and unfamiliar characters.[volume & issue needed]
In their coverage of the storyline, UK Television's Channel 4 News also compared the reaction to "One More Day" to that of Dallas, claiming, "This controversial issue of the comic has been flying off the shelves but reaction from readers has been venomous." Channel 4 speculated that the reason for the storyline was to make the comics more similar to the financially successful films and merchandise.
Comic book historian Peter Sanderson criticized the story for using a supernatural element to retcon the marriage and not maturely dealing with the issue of divorce, arguing the writers had forgotten stories where Spider-Man dealt with his causing the death of Uncle Ben, drugs and child abuse. He wrote, "I expect there are people who are professional comics writers and editors, and people who will someday become professional comics writers and editors, who are outraged that Marvel had Spider-Man make a deal with the devil. And these present and future writers and editors will be determined to undo it. We shall see whether it takes twenty years this time, or much less." He found the story better than the Clone Saga in the respect that it altered an aspect of canon, instead of erasing it entirely. He also criticized the idea of a hero making a deal with one as evil as Mephisto, effectively the devil.
The direct sales estimates for the initial month of publication for the first issue of the storyline, Amazing Spider-Man #544, was 146,215, putting it in second place after "World War Hulk". This dropped to 110,405 with Friendly Neighborhood Spider-Man #24, 100,300 (and seventh position in number of sales) for The Sensational Spider-Man #41 and the conclusion to the storyline, The Amazing Spider-Man #545, was ranked second with estimated sales of 124,481.