Mountainair was founded in 1903 by John Corbett, Col. E.C. Manning, and former Kansas governor E.S. Stover. Because of the Homestead Act of 1889, which brought many settlers into the Estancia Valley and the Atchison, Topeka & Santa Fe Railroad construction of a cutoff route to Belen through the Abo Pass, Mountainair was strategically sited at the peak of summit of Abo Pass. The cutoff was not complete until 1906 and the first passengers rolled through Mountainair in 1907. The Mountainair Depot was active until AT&SF ended services in the late 1960’s.

During this time, pinto bean farming boomed and lasted until the mid 1950’s. Mountainair was known as the “Pinto Bean Capital of the World”. Mountainair held the world’s largest pinto bean processing center and employed hundreds of workers. At peak production 765 carloads, grown on about 45,000 acres, were shipped out in one season. The World Wars boosted production as these beans were shipped overseas to feed American soldiers. The population grew to almost 5000 residents. But in 1946, a ten-year drought struck the region. Because the farmers primarily used rainfall to water the crops, known as “dry land” farming, the drought brought an end to the pinto bean production in the area. Government subsidy was paid to the farmers to not grow anything, so as to preserve the topsoil and protect it from being blown away. This led a shift in the economy from bean farming to ranching.

Today, the railroad no longer maintains a depot in Mountainair since the ATSF, now Burlington Northern & Santa Fe, switched its operations from passenger and mail delivery to solely freight. Despite this, the Town still has a railroad character due to an ever growing number of freight trains still pass through town. The depot, owned by BNSF, is on the Register of Historic Places but is not open to the public.

Water has always been an issue for Mountainair. The choice of its site was based on the needs of the railroad and not on the availability of the natural resource. Early settlers hauled their waters from various locations. Mountainair is above the Chupadera Basin aquifer, which is deep and often undrinkable due to a high concentration of gypsum. Today the primary water supply is in the Estancia Basin aquifer and is pumped from Willard, a tiny hamlet 15 miles northeast of Mountainair.

In addition to the drought, the opening of Interstate 40 caused US Hwy 60 to become a secondary route. These two factors lead to a decline in the population from approximately 5000 to below 1000 residents. But in the 1980’s Mountainair started to attract residents who preferred a rural lifestyle. This slow influx of residents continues today. As of the last census in 2000, the population has risen to 1,116. Today subdivisions are being created beyond town limits that continue to attract new residents to the local area. These subdivisions advertise to their target audience in national media, and Mountainair is experiencing residual benefits from these media campaigns.

Recently, Mountainair has seen a revitalization through the arts. This coupled with the cultural and natural attractions of the Salinas Pueblo Missions National Monuments, Cibola National Forest, and Manzano State Park has seen an increase in tourism to the area. The Salinas Pueblo Missions Monument Visitor Center is located in Mountainair and manages three mission church ruins (Quarai, Abo, and Gran Quivira). Because of the close proximity of the ruins, Mountainair is currently known as “Gateway to Ancient Cities.”