NASCAR's first-ever In-Season Challenge drew 16.6 million total viewers across TNT, truTV and HBO Max over its five-race stretch, according to audience data released this week by TNT Sports. That figure represents a 43% increase compared to the same period in 2025.
The numbers cover the inaugural tournament, which ran as part of the 2026 NASCAR Cup Series season and marked TNT's first year back as a Cup Series broadcaster. The five-race stretch averaged 2.0 million viewers per broadcast. Excluding a weather-affected race in Atlanta that aired after a three-hour, nine-minute delay and produced the latest Cup Series finish in seven years, that average climbed to 2.2 million, an increase of more than 2.1 million viewers over comparable races from last season.
The Atlanta race was an outlier in more ways than one. Every other event in the tournament posted stronger numbers, with two races standing out in particular.
The July 19 race at North Wilkesboro Speedway averaged 2.4 million viewers, making it the second-most watched race under TNT's current NASCAR media rights agreement. That figure was also a 22% increase over Round Four of the 2025 In-Season Challenge. The tournament finale, the Brickyard 400 at Indianapolis Motor Speedway, matched that average with 2.4 million viewers. The Indianapolis broadcast peaked at 3.1 million viewers at 5:15 p.m. ET. Corey Heim won the race, earning his first NASCAR Cup Series victory.
Streaming numbers also moved sharply upward. Minutes watched per subscriber on HBO Max increased by approximately 50% compared to the same period in 2025, reflecting stronger engagement with both race broadcasts and additional NASCAR content. Practice and qualifying coverage across truTV and HBO Max averaged 17% more viewers year over year.
The gains among younger audiences were among the more notable figures TNT released. Adults ages 18-34 watched practice and qualifying coverage at a rate 55% higher than the year before, a demographic that broadcasters track closely when evaluating a sport's long-term reach.
The In-Season Challenge is scheduled to return for a second season in 2027.
