Within a year Cardus had been moved from the reporters' room to take charge of the paper's "Miscellany" column. He also resumed the duties of part-time secretary to Scott, who was at this time over 70, and had edited The Manchester Guardian since 1872. Despite his years, he struck Cardus as "of inexhaustible Energy and aliveness". Scott was a demanding employer, who gave his young Writers free rein, but expected in return long hours and total dedication. Driven hard, sometimes to the point of exhaustion, Cardus nevertheless relished these years, and never complained to Scott of weariness. Early in 1919 his role changed again, when he was made junior drama critic under the direction of C.E. Montague, the paper's principal theatre critic who had returned from war Service with no great Desire to continue in the role. Cardus's principal ambitions still lay in the direction of music criticism, though he recognised that this door was closed while Samuel Langford, music critic since 1906, remained in post. In preparation for any opportunity that might arise in that direction, Cardus maintained a daily two-hour study of music or music literature.

Neville Cardus was born on 3 April 1888 in Rusholme, Manchester. Throughout his childhood and young adulthood he was known as "Fred". There has been confusion over his birth date; some sources give it as 2 April 1889, and Cardus himself hosted a dinner party on 2 April 1959 believing this to be his 70th birthday. His birth certificate, however, confirms the earlier date. Neville's mother was Ada Cardus, one of several daughters of Robert and Ann Cardus of 4 Summer Place, Rusholme. On 14 July 1888, when the baby was three months old, Ada left her parents' home and married John Frederick Newsome, a blacksmith. Apart from their shared forenames, there is no evidence that Newsome was Neville's biological father, who is described in Cardus's autobiographical works as a Violinist in an orchestra. The Newsome marriage was short-lived, and within a few years Ada and Neville had returned to her parents' home in Summer Place.

After Robert Cardus's death in 1900 the family moved several times, eventually breaking up altogether. Cardus left school in 1901 and took a variety of short-term, unskilled jobs before finding more secure employment as a clerk with Flemings' marine insurance agency. He lived for a time with his Aunt Beatrice with whom, according to Brookes, he had at an early age "embarked on a lifelong love affair ... In his eyes she could do no wrong". A flamboyant character, Beatrice brought colour into Cardus's life; she encouraged him to read worthwhile books and her memory, Brookes asserts, "remained a potent inspirational force" throughout his later life as a Writer. She also bought him his first cricket bat.

Alongside his intellectual pursuits Cardus played and followed cricket. As a small boy he had begun to visit Old Trafford Cricket Ground to watch Lancashire matches: "The first cricketer I saw was A.C. MacLaren ... I can still see the swing of MacLaren's bat, the great follow-through finishing high and held there with the body poised". In 1902 he saw the Test match against Australia in which Victor Trumper scored a century before lunch and thereby won a permanent place among Cardus's heroes. Cardus first played cricket on rough waste land close to his home in Rusholme; as he matured he developed as an effective medium-paced off break Bowler, and for several seasons from 1908 onwards he played as a weekend professional in Manchester league cricket. "I am not ashamed to confess that I seldom hesitated, as soon as a batsman came to the crease, to let him have a quick one bang in the penis; after which a quick, simple straight one would invariably remove him from the scene".

Cardus's interest in music began with the popular tunes sung by his mother and her sisters in the family home. He remembered hearing for the first time the melody of the "Vilja" song from Franz Lehár's operetta The Merry Widow, which "curled its way into my heart to stay there for a lifetime". In April 1907 he was "swept ... into the seven seas of music" by a performance of Edward German's operetta Tom Jones. "I am unable to explain", Cardus wrote many years later, "why it should have been left to Edward German—of all composers—to release the flood". He began going to the Hallé Orchestra's concerts at the Free Trade Hall where, on 3 December 1908, he was present at the premiere of Elgar's first symphony, under Hans Richter. He regularly attended the fortnightly concerts at the Royal Manchester College of Music, where students' performances were assessed by the principal, Adolph Brodsky. As part of his scheme of study, Cardus briefly took singing lessons, his only formal instruction in music. In 1912 Cardus published his first musical article, "Bantock and Style in Music", in Musical Opinion.

In the spring of 1912, in search of a change from his unrewarding clerical job, Cardus applied for the post of assistant cricket coach at Shrewsbury School, citing his bowling averages in Manchester club cricket. He reasoned that, by living frugally during the Shrewsbury summers, he would be able to Finance his winter studies of music and literature. His application was successful, and in May 1912 he began his duties. He worked initially under Attewell, a former Nottinghamshire professional, and later under the Yorkshire and England cricketer Ted Wainwright. Cardus established good working relations with both of these, but identified most closely with Cyril Alington, the school's headmaster: "Because of Alington I call myself ... an old Salopian". Alington first detected Cardus's intellectual potential when he found him reading a copy of Gilbert Murray's translation of Euripides's drama Medea. In August 1914, in addition to his cricketing duties he became Alington's secretary, after the previous incumbent joined the army at the outbreak of war; Cardus was rejected for military Service because of his poor eyesight.

Cardus did not find his duties at Shrewsbury onerous. He made frequent trips to Manchester, for Hallé concerts or to watch Thomas Beecham conduct at the Manchester Opera House. He found time for other work; thus, in 1913, he was the music critic for the northern edition of The Daily Citizen. This short-lived newspaper was an official organ of the early Labour Party; mainly out of admiration for Bernard Shaw Cardus had joined the Independent Labour Party, but quickly lost interest in socialism: "Their creed or system was obviously not to be a means to an end but an end in itself". According to Brookes, the influence of Shrewsbury School affected Cardus to the extent that "[t]he playing fields of an English public school were for him a more natural setting than the iconoclastic frenzy of the Lyons café where socialism vied with Richard Strauss for pride of place in the race to modernity". The Daily Citizen paid poorly, and Cardus's association with it soon ended.

In the winter of 1916–17 Cardus continued his private studies while working intermittently; among various jobs, he collected insurance premiums for a burial society. Early in January 1917 he wrote to C. P. Scott, The Manchester Guardian's Editor, asking for any available post at the paper, as "the means whereby to continue my education". To bolster his chances he enclosed specimens of his writing. The result was, first, a temporary unpaid position as Scott's secretary, but in mid-March Scott offered a job on the paper's reporting staff. The Writer J. B. Priestley later asserted that Cardus, who did not know shorthand, was engaged not as a reporter, but as a "writer". In Cardus's own account of these years he appears to have been fully engaged in reporters' duties, his lack of shorthand being dismissed by the chief reporter, Haslam Mills, who paraphrased Shakespeare: "Some men are born to shorthand, others achieve shorthand, while others have shorthand thrust upon them". Mills advised Cardus to concentrate on style: "We can be decorative at times; we can even be amusing. Here, possibly, you will find scope".

In the spring of 1919, while recovering from a serious pulmonary condition, Cardus took up a suggestion from his news Editor, william Percival Crozier, that he should watch some cricket at Old Trafford and, if he felt able, write reports on a few matches. On 19 May 1919 Cardus went to the first day of Lancashire's match with Derbyshire. His first published cricket report, on the following day, showed little sign of his later characteristic style: "I simply had no intention of writing on cricket for any length of time; this was a spare-time affair ... and I fitted myself into the idioms and procedures of the sporting Writers of 1919". Scott nonetheless saw a potential, and from the beginning of 1920 Cardus became the paper's regular cricket correspondent, under the by-line "Cricketer", a position he held for 20 years.

Cardus had been known to Australian readers since the 1920s, when The Argus in Melbourne reported his view that Australians made cricket "a war game ... with an intensity of purpose too deadly for a mere game." His books on cricket were widely reviewed in the Australian press in the 1920s and 30s; one critic commented in 1929, "Mr. Cardus mingles fancy with fact. The latter is preferable." Another Australian Writer, quoting him extensively in 1932, observed, "Mr. Cardus is a gifted Writer and a most impartial critic." By 1936 he was known to a considerable section of the Australian public as a cricket Writer, although he was hardly known there in his musical capacity.

The new sense of financial and professional security was probably instrumental in the decision of Cardus and Edith King to marry, on 17 June 1921. The marriage, which lasted until Edith's death 47 years later, was unconventional; the couple led individual lives and rarely lived together, while remaining devoted friends. Cardus described his wife as "a great spirit and character, born for sisterhood not marriage." From this time onward, Cardus used the forename "Neville" in place of "Fred", and adopted the initials "N.C." for his music reviews, to distinguish this persona from "Cricketer". In August 1921 Cardus gained what he termed "the only scoop of my career", when he reported the unexpected victory by 28 runs of MacLaren's scratch side over the previously unbeaten Australian touring team. The match, at The Saffrons ground at Eastbourne, had attracted little interest from other cricket correspondents, being treated as a foregone conclusion.

Following Langford's death in May 1927, Cardus became The Manchester Guardian's chief music critic. For several years he had worked closely with Langford, whose influence on the younger man was equalled only by that of Ernest Newman, Langford's predecessor as the paper's music critic: "Langford taught me to feel and translate, while Newman taught me to observe and analyse". Cardus's fellow-critic Hugo Cole has described his approach as personal rather than academic, based on his own reactions to the music he was hearing, and with a complete independence of judgement. Cardus was, Cole says, "the last distinguished music critic never to have received formal musical training ... he was a Writer first, and a music critic second".

Cardus often expressed views contrary to popular and critical opinion. He dismissed Stravinsky's The Rite of Spring as "a sophisticated exploitation of primitive rum-ti-tum". When Harty introduced Gershwin's symphonic poem An American in Paris into a Hallé concert, Cardus proposed "a 150 per cent [import] tariff against this sort of American dry-goods". He professed to think that Sullivan's "preoccupation with comic opera, to the neglect of oratorio and symphony" was a "deplorable" loss to English music, although he also wrote that without Gilbert, nothing of Sullivan's music would have survived. Cardus championed Delius against the consensus of his fellow-critics: "His music looks back on days intensely lived through; it knows the pathos of mortal things doomed to fade and vanish". At the 1929 Delius Festival in London, Cardus briefly met the Composer, who thought he looked too young to be The Manchester Guardian's music critic, and counselled him: "Don't read yourself daft. Trust to y'r emotions". Also against the grain of critical opinion, Cardus commended the then unfashionable music of Richard Strauss and Anton Bruckner.

Within the relaxed framework of his marriage, Cardus enjoyed relationships with many women. These included Hilda "Barbe" Ede, with whom he shared a passionate affair in the 1930s before her sudden death in 1937; Cardus referred to her as "Milady", and devoted a chapter of Full Score to her. After his return from Australia his closest women friends were Margaret Hughes and Else Mayer-Lismann, to whom he referred respectively as his "cricket wife" and his "music wife". Hughes, who was more than 30 years younger than Cardus, became his literary executor after his death, and edited several collections of his cricketing and musical writings.

In 1931 Cardus visited the Salzburg Festival, where he met Beecham and began a friendship which lasted until Sir Thomas's death in 1961—despite numerous disagreements. One of Cardus's notices in 1937 so incensed Beecham that he announced he would not conduct any concert at which Cardus was present. Cardus later numbered Beecham, with Elgar and Delius, as "one of the three most original spirits known in English music since Purcell". The annual Salzburg Festival became a highlight of Cardus's musical calendar; in 1936 he saw Toscanini conduct a performance there of Wagner's Die Meistersinger that, he said, "will remain in the mind for a lifetime ... Toscanini held us like children listening to a tale told in the chimney corner, lighted by the glow of olden times". Cardus's final prewar Salzburg visit was in 1938, just after the German-Austrian Anschluss which led to the withdrawal in protest of many of the Festival's leading figures.

Selections from Cardus's Manchester Guardian cricket writings were published in a series of books between 1922 and 1937. Because of financial constraints the paper did not send "Cricketer" to Australia to cover the "Bodyline" tour of 1932–33. Cardus was generally approving of Jardine's controversial bodyline tactics, writing on 5 March 1933: "[H]ad [Jardine] been a weak man, all the Energy of Larwood [England's premier bowler] might have proved as vain a thing as it did in 1930". In 1936–37, Cardus accompanied the MCC team to Australia; otherwise he continued to write on English domestic cricket until the 1939 season was summarily truncated. On 1 September, the day that Germany invaded Poland, Cardus observed the removal of the bust of W. G. Grace from the Lord's pavilion; he was informed by a bystander: "That means war".

The 1936–37 MCC tour of Australia under G.O. Allen was the occasion of Cardus's first visit to the country. During the tour he made, or consolidated, friendships with players and colleagues including C. B. Fry and Donald Bradman. Fry, a former England cricket captain, was a boyhood hero of Cardus, and was covering the Tests for the London Evening Standard. In Bradman, Cardus found a sophistication and sensitivity that other Writers had failed to detect. When interviewed on his arrival in Australia, Cardus speculated how he would cope for the six months of the tour without music; he was touched when the following day music students in Perth gave him a private recital of music by Chopin and Hugo Wolf. During this tour Cardus wrote for The Herald in Melbourne, and broadcast about cricket on Australian radio.

Cardus made a private visit to Australia from mid-January to mid-March 1938. When he joined The Herald in 1940, his initial brief was to cover a series of concerts conducted by Beecham for the Australian Broadcasting Commission (ABC). Daily contact between the two men during Beecham's time in Australia between June and October 1940 helped to consolidate their friendship. At the end of his tour Beecham tried to persuade Cardus to join him in sailing to America, asking, "Do you propose to stay in this barbarous country all your life?" Cardus insisted on remaining in Australia, but moved from Melbourne to Sydney. Concluding that he could not satisfactorily review concerts for an evening newspaper, he joined the staff of The Sydney Morning Herald (SMH).

Despite financial incentives from London newspapers, Cardus remained loyal to The Manchester Guardian. On the outbreak of war in September 1939 the Free Trade Hall closed, requisitioned for military purposes. The Hallé Society left Manchester to tour with Sargent around the north-west of England. With no music in Manchester and all first-class cricket suspended, Cardus was unemployed, "imprisoned in Manchester, useless to anybody". Thus, when he received an offer from Sir Keith Murdoch to join The Herald of Melbourne in Australia, he accepted immediately.

Early in 1942 Cardus rented a small flat in the Kings Cross district of Sydney, where he wrote his Ten Composers (1945) and Autobiography (1947). He said later that he found the discipline of writing for seven hours a day difficult at first, but that the process had turned him from a Journalist into something more substantial. When later in 1942 his wife announced her intention of sailing from England to join him, Cardus declined to move to a larger flat to accommodate them both, and rented a separate establishment for her a mile away. They dined together once a week, but otherwise continued to lead largely separate lives.

By the end of the war Cardus's thoughts were turning to England. Refusing an offer of a highly paid permanent contract to cover both music and cricket for the SMH he considered his options; with some reluctance he agreed to cover the MCC's 1946–47 tour of Australia for the SMH and also for The Times and The Manchester Guardian. The Novelist Charles Morgan wrote of Cardus's reports, "the best [I have] read these 40 years. Who shall dare to say now that George Meredith is forgotten?"

In April 1947 Cardus returned to England. He had not as yet decided to leave Australia permanently, but "felt in need of spiritual refreshment". He found a war-weary England in which much had changed; familiar landmarks had disappeared, and old friends and acquaintances had died. The Free Trade Hall was a burnt-out shell, and the Queen's Hall in London completely destroyed; however, Cardus was struck by the apparent good health of the English music scene. He also found an undamaged Lord's, and enjoyed a season of magnificent cricket, marked by the batting exploits of the Middlesex pair, Denis Compton and Bill Edrich. Cardus was back in Sydney by the end of the year, but early in 1948, having accepted an offer from The Sunday Times to cover that year's Test series against Australia, he left for England again.

Another factor that brought Cardus to England in 1948 was the prospect of succeeding Newman, whose retirement as chief music critic of The Sunday Times was assumed to be imminent. However, Newman had no intention of retiring, and made it clear that he would resent any successor-designate looking over his shoulder. Feeling slighted, Cardus resigned from the paper and accepted an offer from the London Evening Standard to be its music critic. This new appointment was short-lived; Cardus's lengthy and discursive concert reviews were incompatible with this paper's style, and were ruthlessly cut by subeditors. At the end of 1948 he was back in Australia, proclaiming his intention to settle there permanently. This determination, too, was brief; the lure of London life proved irresistible. Because of the commercial success of his Autobiography, published in 1947, and the immediate commissioning of a second autobiographical work, Cardus was not under immediate financial pressure. He left Australia again in the spring of 1949, and although he spent the English winter of 1950–51 in Australia, writing about the 1950–51 England v. Australia Test series for the Sydney Morning Herald, London was thereafter his permanent home. Here he worked as a freelance Writer, in which role he resumed his association with The Manchester Guardian. In December 1951 he was appointed the paper's London music critic, on a permanent salaried basis.

In 1949 Cardus set up his London home at the National Liberal Club, while Edith took a flat in Bickenhall Mansions, just off Baker Street. The pair lived harmoniously apart, though in frequent contact, until Edith's death. Cardus found London's musical life invigorating, with five major orchestras and a host of distinguished conductors and solo artists performing regularly. Toscanini paid his final visit to England in 1952, with two concerts at the Royal Festival Hall. Outside London, Cardus was a regular visitor to the Edinburgh Festival and to Glyndebourne, and was in Manchester for the reopening of the Free Trade Hall and the "homecoming" of the Hallé Orchestra in November 1951. The inaugural concert concluded with Kathleen Ferrier singing "Land of Hope and Glory". Cardus had first heard Ferrier at the Edinburgh Festival in 1947; he became a devoted admirer to the extent that, eventually, questions were raised about his critical blindness to her technical weaknesses. He wrote of her singing that it was, "like the woman herself ... imbued with a quiet but reliant sense and a feeling for the fun and goodness of life". He was devastated by her death from cancer in October 1953; the following year he edited and contributed to a memorial volume of tributes.

Throughout the 1950s and 1960s Cardus wrote cricket articles; these included an annual reflection for Wisden Cricketers' Almanack and occasional columns for The Manchester Guardian, for whom he covered the 1953 Test Matches against Australia. In the English winter of 1954–55 Cardus made his final visit to Australia, to report on the Test series for The Sydney Morning Herald; he undertook to write "impressions" rather than day-to-day reports on play. He found time to enjoy Sydney's theatrical and music scene, but was disappointed in what he perceived as a decline in the city's musical standards.

Cardus was not an "establishment" figure. His friends encountered initial resistance when they sought his election to the MCC, although he was eventually accepted in 1958. He was denied the civic honour of the Freedom of the City of Manchester, and although he made light of this omission he was hurt by it. Long after his death, the city named a pathway close to the rebuilt Summer Place "Neville Cardus Walk". Aside from formal institutional recognition, Cardus was highly regarded by prominent individual cricketers and Musicians, as indicated by the "tribute book" he received at his 70th birthday celebration lunch. The book included contributions from Wilfred Rhodes, Jack Hobbs and Len Hutton, and also from Klemperer, Elisabeth Schwarzkopf and Bruno Walter. He managed to maintain close friendships with both Beecham and Sir John Barbirolli, though the two conductors cordially disliked one another.

In the decades after the war many of Cardus's earlier heroes and acquaintances died. On Fry's death in 1956 Cardus wrote of him as "A great Englishman, measured by any standards of occupation, art and civilisation". In 1959, still in harness, Newman died at the age of 90; Cardus considered him the most outstanding of all music critics, and thought he should have been appointed a Companion of Honour (CH), or even to the Order of Merit. Beecham died on 8 March 1961. Cardus had for some years noted a decline in his old friend's powers, though he had written in 1954, on the occasion of Beecham's 75th birthday, of the debt the music world owed to the conductor: "He led us out of the Teutonic captivity. He showed us other and more sensitive worlds". After Beecham's death, Cardus organised the publication of a celebratory memoir, as he had done with Kathleen Ferrier. To an extent the departed idols were replaced with new heroes: in music, Herbert von Karajan, Otto Klemperer, Clifford Curzon and Claudio Arrau; in cricket, Keith Miller and Garfield Sobers. Cardus maintained a keen antagonism towards much of contemporary music; discussing Pierre Boulez's Pli selon pli after a performance in 1965, he said he "could not relate the varied succession of aural phenomena to music as my musical intelligence and senses recognise music".

Beside his CBE and knighthood, Cardus received numerous honours from the musical and cricketing worlds, at home and overseas. In 1963 he was awarded the City of Bayreuth's Wagner Medal; he was given honorary membership of the Royal Manchester College of Music in 1968, and of the Royal Academy of Music in 1972. The Hallé Orchestra honoured him with two special concerts in April 1966 to mark his long association with the orchestra. In 1970 he received the Austrian Cross of Honour for Science and Art, 1st class. Among the honours he most valued was the presidency of Lancashire County Cricket Club, which he accepted in 1971.

In 1964 Cardus was appointed a Commander of the Order of the British Empire (CBE). In a letter to his friend Marjorie Robinson he described the investiture at Buckingham Palace, remarking that the Queen "might have been any nice shy young lady in D.H. Evans or Kendal Milnes". Just over two years later Cardus was awarded a knighthood, the first music critic to receive such an honour, although in all likelihood it was awarded as much for his cricket writing. Years previously Beecham had advised: "In the unlikely event of you being offered a knighthood, Neville, take it. It makes tables at the Savoy so much easier to come by".

Edith Cardus died on 26 March 1968. Despite their separate day-to-day lives, she had been an influential presence for nearly all Cardus's adult life; they had communicated by telephone almost daily, and he felt her loss keenly. After her death he left the National Liberal Club and moved into her flat, which remained his base for the rest of his life. In the ensuing months he worried about his deteriorating relationship with The Guardian; the paper had been renamed in 1959 following reorganisation, and its editorial offices had moved to London in 1964. Cardus felt that much of the old ethos had departed, and that his once-sacrosanct copy was now at the mercy of subeditors. He was particularly incensed by the treatment meted out to his 1969 Edinburgh Festival reports, and referred to the subeditors' room as "the Abattoir" in one of many letters complaining of editorial butchery.

As well as his work for The Guardian Cardus wrote occasionally for The Sunday Times, a particular pleasure to him in view of his failure to achieve Newman's post. In 1970 he published Full Score, the last of his autobiographical works and, in Daniels's view, the least substantial of all the Cardus books. In his eighties, Cardus assumed the role of guru to young aspiring Writers, before whom he would hold court in favourite locations: the Garrick Club, the National Liberal Club, or Lord's. According to Daniels, Cardus "thrived in the role of patron, encourager, [and] accoucheur". Howat describes his appearance in these years as not having changed much from his younger days: "... the lean, ascetic figure of moderate height, with sharp features, sleek hair, and strong glasses".

Cardus died on 28 February 1975 at the Nuffield Clinic, London, a few days after collapsing at home. His cremation Service was private. On 4 April more than 200 people attended a memorial Service at St Paul's, Covent Garden. These included representatives from Cardus's worlds of cricket, journalism and music. Flora Robson and Wendy Hiller gave readings, and Clifford Curzon, with the Royal Philharmonic Orchestra, played the second movement of Mozart's Piano Concerto No. 23. The eulogy was given by the cricket Writer and Historian Alan Gibson, who took as his text verses from Blake's Auguries of Innocence:

In the conventional sense, Cardus was not a religious man; Dennis Silk, a one-time MCC President, suggests that Cardus's religion was "friendship". In Autobiography Cardus says he found his Kingdom of Heaven in the arts, "the only religion that is real and, once found, omnipresent"—though his rationalism was shaken, he confesses, when he came to understand the late string quartets of Beethoven. He ends his autobiography by declaring: "If I know that my Redeemer liveth it is not on the church's testimony, but because of what Handel affirms".