While Cramer cut a few solo sides in 1953, his most important work in the early '50s was as a session musician, where he first met Chet Atkins, who encouraged the pianist to move to Nashville. He did in 1955, rejoining Atkins as the house pianist at RCA Records to begin developing what would ultimately be recognized as the Nashville sound, a style shorn of the elements associated with traditional country and honky tonk instead favoring a more polished, progressive sheen. With Atkins behind the production boards, Cramer began to perfect his unique style of playing, a method not dissimilar to guitar-picking in that he would hit one key and then slide his finger onto the next, creating a blue, lonesome sound. Under Atkins' guidance, Cramer played on hundreds of sessions, including many for Presley, among them "Heartbreak Hotel."

In 1957, Cramer released his own solo debut, That Honky-Tonk Piano, and in the next year scored a minor pop hit with the single "Flip, Flop and Bop." As his solo career was largely secondary in relation to his session work, he recorded his own music sporadically, but in 1960 notched a significant country and pop hit with the self-penned instrumental "Last Date." The follow-up, a cover of Bob Wills' "San Antonio Rose," reached the Top Ten of both charts. He also released an LP a year between 1960 and 1962, starting with Hello Blues and followed by Last Date and I Remember Hank Williams.

From 1965 to 1974, Cramer annually released a Class Of... album, a collection of the year's top hits done in his own inimitable style. In 1971, he also teamed with Atkins and saxophonist Boots Randolph for the album Chet, Floyd and Boots. By 1977, Cramer was exploring modern technology, and on the LP Keyboard Kick Band, he played a number of instruments, including a synthesizer. In 1980, he released his last significant hit, a recording of the theme from the hit TV drama Dallas. Though largely quiet for most of the decade, in 1988 Cramer released three separate albums -- Country Gold, Just Me and My Piano!, and Special Songs of Love. He died December 31, 1997.