In 1931, in the midst of the Great Depression, a handful of entrepreneurs founded Southwest Gas Corporation, and soon after began selling liquefied petroleum gas (LPG) in the dusty railroad town of Barstow, California. Although the fledgling company soon expanded to nearby Victorville, uncertain economic conditions limited its growth potential during the Depression.

Southwest Gas grew slowly but steadily over the next 20 years, serving these two High Desert communities. Then, in 1951, Pacific Gas & Electric Company built a high-pressure natural gas transmission line from San Francisco to the Arizona border, where it linked up with El Paso Natural Gas Company's line from Texas. Recognizing the growth potential offered by clean, efficient, economical natural gas, Southwest tapped into the new line and converted its system to the more marketable fuel. This would become a significant milestone in a truly remarkable business success story.

Three years later, the company expanded eastward, bringing natural gas service to the cotton-farming and copper-mining regions of central Arizona, as well as to the industrial plants in Henderson, Nevada, and the small-but-growing gaming oasis of Las Vegas. The growth potential and centralized location of Las Vegas enticed company owners to move the corporate headquarters from Los Angeles to the burgeoning desert community in 1958.

In 1959, Southwest purchased another small LPG company, this one in Big Bear Lake, California, a popular resort destination for those looking to escape the hustle and bustle of Los Angeles. Seeing the potential to serve the more than 3,000 homes in the area, Southwest soon converted the Big Bear LPG system to natural gas as well.

In 1963, the company brought natural gas service to northern Nevada, constructing a new natural gas transmission line from the Idaho border westward across the northern tier of the state to the Carson City/Reno-Sparks area as well as Lake Tahoe. Along the way, mining and farming communities from Elko to Yerington were converted to natural gas service.

Over the next 15 years, the company continued its steady growth, and by 1978 was serving more than 150,000 customers in three states. The company's most significant growth was yet to come, however. In 1979, Southwest nearly doubled its size overnight with the acquisition of the gas system owned by Tucson Gas & Electric Company in southern Arizona. The acquisition added more than 140,000 customers to the company's system and ended a two-year moratorium on new natural gas hook-ups in the Tucson area.

Just five years later, in 1984, Southwest again doubled its size with the purchase of the natural gas properties of Arizona Public Service Company in central Arizona, including metropolitan Phoenix and surrounding communities. This acquisition added some 300,000 customers to the company's customer base, bringing its total customer count to more than 600,000. In little more than five years, the company had grown fourfold!

Still another acquisition occurred in 1991 with the purchase of the natural gas properties of CP National Corporation in Henderson, Nevada and Needles, California. This added nearly 12,000 customers to Southwest's system and made the company the sole natural gas utility in southern Nevada.

By the end of 1995, Southwest's customer count had surpassed the one million mark, quite a feat for a company that had begun so humbly just 64 years before.