Gifford attended the public schools of Salem and entered Harvard at the age of fifteen, in September 1901, completing the four-year course in 1904 but taking his degree with the class of 1905.
Rejecting the advice of his father, who reflected the anticorporation bias then prevalent among small businessmen, Gifford took a job as an accounting clerk with the Western Electric Company in Chicago. He quickly showed a tendency to think innovatively and soon introduced improved ways of doing the simple arithmetical calculations that the work of his office required. He had an innate respect for data of all kinds and constantly analyzed figures to derive previously obscure facts about the efficiency of the company. In a rapidly growing enterprise, his initiative and steady devotion to work were quick to be noted. Just before his twenty-first birthday, he was made assistant secretary and treasurer of the company. Gifford left Western Electric for six months in 1911 to run an Arizona copper mine. Theodore N. Vail, who had helped set up the American Telephone and Telegraph Company (AT&T) in 1885, had had his eye on Gifford for some time. When Gifford decided to return to the company, Vail made him chief statistician at a salary of $7, 000 a year. In 1915, Gifford enrolled in the civilian military training school at Plattsburgh, New York, but this was as close to a uniform as he would ever get. At the recommendation of Howard E. Coffin of the Hudson Motor Car Company, President Woodrow Wilson named Gifford supervising director of the Committee on Industrial Preparedness of the Naval Consulting Board. His task was to make a survey of the capacities of American factories for production of war matériel. The report led to the creation of the Council of National Defense and a related advisory commission. Gifford had to end his honeymoon early in order to move to Washington, D. C. , to organize the council. Just before the war ended, he went to France to organize the Inter-Allied Munitions Council to coordinate aircraft production. When Gifford returned to AT&T after the Armistice, his responsibilities increased quickly. He was named controller of the company and, in 1920, vice-president in charge of finance. It was his job to raise the money to finance the Bell System's phenomenal growth, and during the 1920's the modern telephone system took shape. He scored a notable triumph in placing a $90 million stock issue directly with small investors by selling the shares, which he knew would have more appeal than savings bank accounts, through local offices of the telephone company. He emphasized the unique position of the company in the American business world, which was virtually that of a natural monopoly. In 1922, Gifford became a director of AT&T, then executive vice-president, and, on January 20, 1925, the third president of the company. The sheer size of the Bell System and its scientific complexities and social ramifications made organization Gifford's chief concern. He saw the need for fundamental organizational changes and policy rethinking. He initiated a policy of divestment of all activities that did not fit an avowed policy of furnishing a network, both local and long-distance, of wired voice communication facilities and the design, manufacture, and installation of the equipment such a network required. He sold International Western Electric, having concluded that AT&T would do well to remain aloof from government-dominated foreign telephone enterprises; the Graybar Electric Company, a wholesale jobber that had been set up to market and maintain a host of unrelated electrical equipment; and radio station WEAF in New York City, which the company had established early in the 1920's, when commercial radio was in its infancy. Western Union, the giant telegraph company that had been acquired a few years before, was also dropped because it did not fit Gifford's plans. Meanwhile, such inventions as the teletype and the telephoto were acquired. The attainment of nearly universal residential subscribership and conversion to the dial system of automatic switching were the most important developments during Gifford's long presidency. The switch to dialing was accomplished, moreover, without discharging a single operator. During the depression, AT&T profits sometimes failed to equal the dividend rate, but Gifford showed that his longtime policy of adding surplus profits to retained surplus made it possible to avoid cutting dividends. Gifford's one major failure in his career was his inability to coordinate unemployment relief in the fall of 1931 at the request of President Herbert Hoover, who was determined to keep such relief on a state and local basis. In World War II, Gifford was again active in war production planning. Returning to AT&T in 1945, he set the company on a course of expansion that made all previous records seem petty. At the age of sixty-three he became chairman of the board and two years later he retired. He died in New York City on May 7, 1966.
Although Gifford was a lifelong Republican, President Harry S. Truman appointed him ambassador to Great Britain.
Gifford was a quiet, reserved man who detested large social gatherings. A neat, conservative dresser who was unswervingly loyal to dark suits and bow ties, Gifford lived a rather lonely life in a city town house and on weekends at his country estate in North Castle, Westchester County, New York.
Gifford married Florence Pitman on October 28, 1916. He and his wife, who had two children, were divorced in 1929, for Gifford failed to give his wife the kind of life she wanted. On December 22, 1944, he married a widow, Augustine Lloyd Perry.