After a visit to Chicago, Ritter decided to continue his law studies at Northwestern University's law school in 1929. He was unable to continue with the course due to lack of money and left to join a touring production of The New Moon in 1930.
In 1932, Ritter sang on NBC radio and also played the part of Sagebrush Charlie in a Broadway production of The Roundup and Mother Lode. He also worked on various radio programs, sang songs, and told tales of the Old West in Lone Star Rangers. He also appeared in several radio dramas, including CBS's Bobby Benson's Adventures and Death Valley Days. In 1933, Ritter starred in a children's cowboy radio show on WINS radio in New York called Cowboy Tom's Roundup. These shows marked the beginning of Ritter's popularity in radio, which paved the way for his upcoming singing career.
Ritter made four recordings for the American Record Corporation in 1933 but only the song "Rye Whiskey" was released; shortly thereafter, he moved to Decca Records, where he made his first original recordings, "Sam Hall" and "Get Along Little Dogie", in 1935. He went on to record a total of 29 songs for Decca, the last being in 1939 in Los Angeles as part of Tex Ritter and His Texans.
Ritter, in addition to being a singer and theatre actor, was also a movie actor in B-grade western movies. These included Song Of The Gringo, Headin' For The Rio Grande, and Trouble In Texas (1937), which he co-starred with Rita Hayworth (then known as Rita Cansino). In 1938, after starring in Utah Trail, Ritter left the financially-troubled Grand National film company; between 1938 and 1945, he starred in around 40 "singing cowboy" movies, most to critical scorn.
In 1942, Ritter's music recording career began what was his most successful period as an artist. He achieved significant success with "Jingle, Jangle, Jingle", and in 1944, he scored another hit with "I'm Wastin' My Tears On You", which hit #1 on the country charts and #11 on the popular music charts. "There's A New Moon Over My Shoulder" was a country #2 and pop charts #21. Between 1945 and 1946, he registered seven consecutive Top 5 hits, including "You Two Timed Me One Time Too Often", a country number 1 which spent 11 weeks on the charts. In 1948, "Rye Whiskey" and his cover of "Deck Of Cards" both made the Top 10 and "Pecos Bill" reached #15. In 1950, "Daddy's Last Letter (Private First Class John H. McCormick)" also became a hit. In 1952, the movie title-track song "High Noon" became a hit even after it seemed that his days of hit songs were over; the song received an Oscar for Best Title Song that year.
Even after the peak of his performing career, Ritter would be recognized for his contributions to country and Western music and for his artistic versatility. In 1963, Ritter became one of the founding members of the Country Music Association. In 1964, he became the fifth person and first singing cowboy to be elected to the Country Music Hall of Fame. He also received a lifetime membership to the Grand Ole Opry. In 1974, Ritter had a heart attack while arranging to bail a friend out of jail and died. His song "The Americans" became a posthumous hit shortly after his death.
His younger son, John Ritter, was a notable American television actor best known for his role on the show Three's Company (aired from 1977 to 1984.)