De Kalb is a city in Bowie County, Texas, United States. The population was 1,699 at the 2010 census. It is part of the Texarkana, Texas - Texarkana, Arkansas Metropolitan Statistical Area. Its two area codes are 430 and 903. Its ZIP code is 75559. It is in the Central Time Zone.De Kalb was the birthplace of Bonanza star Dan Blocker, who played the character "Hoss Cartwright" on the popular NBC television Western. De Kalb is also the hometown of former major league baseball player Luke Walker.Singer Ricky Nelson was killed in an airplane crash near De Kalb on December 31, 1985, while he was en route to a concert in Dallas. The tail of the plane is kept at the Williams House museum, along with memorabilia of Nelson's career. The Williams House Museum also houses artifacts and other collections from any of the town's people and those from surrounding communities.