Thunderball was published on 27 March 1961 in the UK as a hardcover edition by publishers Jonathan Cape; it was 253 pages long and cost 15 shillings. 50,938 copies were printed and quickly sold out. Thunderball was published in the US by Viking Press and sold better than any of the previous Bond books. Publishers Jonathan Cape spent £2,000 (£39,760 in 2015 pounds) on advance publicity. Cape sent out 130 review copies to critics and others and 32,000 copies of the novel had been sent to 864 UK booksellers and 603 outside the UK.
|“||The title of the book will be Thunderball. It is immensely long, immensely dull and only your jacket can save it!||”|
—Ian Fleming, in a letter to cover artist Richard Chopping
Artist Richard Chopping once again provided the cover art for the novel. On 20 July 1960 Fleming wrote to Chopping to ask if he could undertake the art for the next book, agreeing on a fee of 200 guineas, saying that "I will ask [Jonathan Cape] to produce an elegant skeleton hand and an elegant Queen of Hearts. As to the dagger, I really have no strong views. I had thought of the ordinary flick knife as used by teenagers on people like you and me, but if you have a nice dagger in mind please let us use it. The title of the book will be Thunderball. It is immensely long, immensely dull and only your jacket can save it!"
Thunderball was generally well received by the critics; Francis Iles, writing in The Guardian wrote that it "is a good, tough, straightforward thriller on perfectly conventional lines." Referring to the negative publicity that surrounded Dr. No—in particular the article by Paul Johnson in the New Statesman entitled, "Sex, Snobbery and Sadism"—Iles was left "wondering what all the fuss is about", noting that "there is no more sadism nor sex than is expected of the author of this kind of thriller". Peter Duval Smith, writing in Financial Times, also took the opportunity to defend Fleming's work against negative criticism, also specifically naming Paul Johnson and his review: "one should not make a cult of Fleming's novels: a day-dream is a day-dream; but nor should one make the mistake of supposing he does not know what he is doing." Duval Smith thought that Thunderball was "an exciting story is skilfully told", with "a romantic sub-plot ... and the denouement involves great events" He also considered it "the best written since Diamonds Are Forever, four books back. It has pace and humour and style. The violence is not so unrelenting as usual: an improvement, I think." He also expressed concern for the central character, saying "I was glad to see him [Bond] in such good form. Earlier he seemed to be softening up. He was having bad hangovers on half-a-bottle of whisky a day, which I don't call a lot, unless he wasn't eating properly."
Writing in The Times Literary Supplement, Phillip Stead thought that Fleming "continues uninhibitedly to deploy his story-telling talents within the limits of the Commander Bond formula." Stead saw that the hijacking of the two bombs "gives Bond some anxiety but, needless to say, does not prevent him from having a good deal of fun in luxury surroundings", whilst "the usual beatings-up, modern style, are ingeniously administered to lady and gentleman like". As to why the novels were so appealing, Stead considered that "Mr. Fleming's special magic lies in his power to impart sophistication to his mighty nonsense; his fantasies connect with up-to-date and lively knowledge of places and of the general sphere of crime and espionage." Overall, in Stead's opinion, with Thunderball "the mixture, exotic as ever, generates an extravagant and exhilarating tale and Bond connoisseurs will be glad to have it." The critic for The Times wrote that Thunderball "relies for its kicks far less than did Dr. No or Goldfinger on sadism and a slightly condescending sophistication." The upshot, in the critic's opinion, was that "the mixture—of good living, sex and violent action—is as before, but this is a highly polished performance, with an ingenious plot well documented and plenty of excitement."
Writing in The Washington Post, Harold Kneeland noted that Thunderball was "Not top Fleming, but still well ahead of the pack", whilst Charles Poore, writing in The New York Times considered the Bond novels to be "post-Dostoevskian ventures in crime and punishment". Thunderball he found to be "a mystery story, a thriller, a chiller and a pleasure to read." Poore identified aspects of the author's technique to be part of the success, saying "the suspense and the surprises that animate the novel arise from the conceits with which Mr. Fleming decorates his tapestry of thieving and deceiving".
The critic from The Sunday Times considered Fleming to have "a sensational imagination, but informed by style, zest and—above all—knowledge". Anthony Boucher wrote that "As usual, Ian Fleming has less story to tell in 90,000 words than Buchan managed in 40,000; but Thunderball is still an extravagant adventure". The critic for the Daily Herald implored "Hey!—that man is taking his clothes off again. So is the girl ... Can anybody stop this? Unfortunately not. Not this side of the best-seller lists. I don't envy Mr Bond's wealthy creator, Ian Fleming. I wish I could pity him", whilst L.G. Offord considered Thunderball to be "just about as wild as ever, with a walloping climax."