By Laura Cooper

America's top brewers see big business in small beers.

Sierra Nevada and Modelo-maker Constellation Brands are among the companies rolling out smaller cans and bottles, known as ponies, and sales are growing, say industry analysts and executives.

The beers are taking up residence during the important summer selling season. The week of July 4 is generally a standout for the industry, with beer sales running roughly 37% above average, according to the Beer Institute, a trade group.

"We're bullish on what ponies can add," said Craig Purser, chief executive of the National Beer Wholesalers Association, which represents more than 3,000 beer and beverage distributors. "Consumers don't have to make a 12-ounce decision."

Sierra Nevada, which introduced its small-can Pils brew last fall, quickly found that it was a strong seller. The company, which sells the beer in eight-can packs, has since decided to sell the small cans in packs of 16 in select markets this fall.

"The piece we didn't fully appreciate is how the size would appeal more broadly to folks who want to moderate," said Ellie Preslar, Sierra Nevada's chief growth officer. "I hear it from fellow parents who want to moderate. They still want a beer at night but are still parenting their kids, so it allows them to have a treat to themselves."

The name "pony" dates back to the late 19th century, according to Molson Coors. It is commonly used as a synonym for small: Kegs are a half barrel of beer, while pony kegs are a quarter barrel, Purser said. Pony cans and bottles are also known as "throw-downs" and "grenades."

Coors is credited with introducing the first aluminum-can pony in the late 1950s. Ponies of Rolling Rock were popular in the 1980s.

Smaller brews are taking on new life now, as many drinkers cut back on their spending and alcohol consumption. The beers range in size from 7 to 9 ounces, smaller than the typical 12- or 16-ounce cans and bottles sold in packs across the U.S. They are similar in size to soft-drink peers that offer 7.5 ounces of Coca-Cola, Pepsi and other beverages in mini cans that are growing in popularity.

Nick Fink, chief executive of Constellation, said the company has been in the small-beer world for more than a decade.

"We're leaning in to it. I think you'll see extensions into it," Fink said. He added that the use of GLP-1 drugs for weight loss offers an opportunity to expand the utility of small beers and move into little-treat culture. "I think it's a particularly exciting play for us."

Osvaldo De La Garza, who lives in the Tampa, Fla., area, is a loyalist of Coronita, a smaller version of the Mexican lager Corona. He keeps his poolside cooler stocked with them. "The little ones are perfect. I take them everywhere, even a little get-together. They're the perfect size," De La Garza said.

De La Garza, 32 years old, said he has been drinking the 7-ounce beers for about two years and doesn't plan to switch back to regular-size Coronas. His wife, he said, finds them cute.

Generating momentum for any type of product is critical for the beer industry. Through April of this year, domestic beer shipments were down 1.6% compared with the same period last year, according to data analyzed by consulting firm Bump Williams.

And while there has been sales momentum around smaller container sizes, their share of the beer market remains small, according to Bump Williams.

Earlier this year, Bud Light released a Post Malone-branded, limited-edition miniature can, pushing the idea that beer in smaller cans stays cold while you drink. Molson Coors has seen its sales of Miller High Life pony bottles grow steadily over the past five years.

Constellation is now putting Pacifico into 7-ounce containers, after success with Coronitas and Modelitos. About seven million cases of Coronita are sold each year, according to Constellation.

Greg McLeod runs a Florida beverage-distribution company and delivers brews to about 3,000 stores. McLeod, president of Pepin Distributing, said he has seen sales of the smaller beers outpace many other beer-package sizes. In hot and humid Florida, McLeod said, residents love the smaller container, because "they can put it on ice and consume it in less time, which means it's always cold."

McLeod said in the 1990s, he did bar promotions around the smaller beers in the Washington, D.C., area. Those promotions are starting to come back, he said.

Write to Laura Cooper at laura.cooper@wsj.com