U.S. auto sales could decline by more than 2 million units by 2040, according to an analysis by Bain & Company. The projection cites falling birth rates, high vehicle prices, aging vehicles, and shifts in consumer behavior.

Mark Gottfredson, a partner at Bain & Company, stated that the automotive industry has historically relied on an annual 1% growth rate tracking overall population increases. "It is the perfect storm, isn't it. It starts with the population declines. You're no longer a growth industry. You're a declining industry. You're a declining industry at a time when the technology is disrupting everything," Gottfredson said.

The Centers for Disease Control considers a fertility rate of 2.1 births per woman to be the replacement rate. In 2025, the U.S. fertility rate was approximately 1.6 births per woman. Bain & Company cited a historical average of about one million people immigrating to the U.S. annually and expects restrictive immigration policies to persist for the next 15 years, potentially cutting net migration rates in half.

Gottfredson noted that half of 16-year-olds currently do not possess a driver's license, compared with nearly 70% between 1966 and 1984. Bain & Company research suggests most individuals still obtain licenses by age 25. According to S&P Global Mobility, the share of new vehicle registrations for those aged 18 to 34 decreased from 12% in the first quarter of 2021 to under 10% by mid-2025.

Craig Daitch, founder and president of Telemetry, stated that new vehicle monthly payments have increased by 30% over four years, with nearly one in five now exceeding $1,000. "The engine behind it is affordability," Daitch said. Sam Fiorani, vice president of global vehicle forecasting for AutoForecast Solutions, said, "When you look into the future, younger people are more likely to use Uber or Lyft when they're going somewhere. We're still seeing groups of young people who enjoy driving and want a new car, but fewer can afford it."

Bain & Company projects that if robotaxis become widely available within 15 years, the proportion of the licensed population could fall by 2 to 3 percentage points to 85%. The firm also projects vehicles per driver could decrease from 1.2 to 1.1. Gottfredson revised earlier projections targeting 2030 for sales volumes to fall below 14 million, citing autonomous vehicles arriving later than anticipated. "We already know how many people have been born and how many people will be of vehicle driving age at age 16 in 16 years from now," he said. "And so we can say with quite a bit of certainty that when we get to 2040, we're going to see we're going to see some decline in the U.S. That decline is even worse in places like Europe and in places like most of the countries in Asia."

In 2015, 17.6 million cars, trucks, and SUVs were sold in the U.S. Vehicle longevity reached a record 12.8 years on the road in 2025, according to S&P Global Mobility. The Bain report indicated the vehicle deregistration rate was about 6% in 2000 and approximately 5% as of 2025. Gottfredson stated the rate could decrease to 4.4% by 2040.