Nielsen is formally adopting its planned additions to its media measurement, and those shifts will carry sizable weight across sports media just as a jam-packed fall event calendar begins.
Effective Aug. 31, Nielsen will make a new co-viewing methodology part of its official audience measurements, known within the media business as “currency.” The new system is aimed at providing greater clarity on group viewing patterns and follows a pilot program conducted early this year.
Before this latest change, the NFL consistently had issues with Nielsen on this particular topic. The league has long felt that its audiences, though by far the largest in all of U.S. television, were still being undercounted amid the hefty group-watching inherent to football fandom.
Now, Nielsen has made three major shifts to its audience measurement methods in the last two years following its introduction of expanded out-of-home tabulation in February 2025 and the September 2025 rollout of Big Data + Panel process.
“The goal is to have the most accurate data, and this definitely is a big step forward,” Nielsen SVP Brian Fuhrer told Front Office Sports. “We think this latest step is going to have a fairly significant impact across the industry.”
Expected Impacts
The co-viewing pilot program from earlier this year yielded an average 4.19% viewership lift for a series of marquee events in February, including Super Bowl LX, the opening and closing ceremonies of the 2026 Winter Olympics, the gold medal game in men’s hockey from those Olympics in Italy, the Daytona 500, and the State of the Union Address.
Had that expanded co-viewing measurement previously been part of the official audience measurements—it won’t be until at least the new television season—Super Bowl LX would have set a new record for the largest audience in U.S. television history.
This initial boost is less than the 10% to 15% increases and bevy of new viewership records generally seen in sports during the 11 months since Big Data + Panel was first implemented. But given the scale of top live sports, even a 4% hike in viewership can result in billion-dollar swings in rights-fee values over time.
The initial months of this latest Nielsen update will include the start and bulk of the 2026 NFL and college football regular seasons, the MLB postseason, the start of the 2026–27 NBA and NHL seasons, and the WNBA playoffs.
CBS Sports, the most-watched NFL rights holder, said it applauds the latest Nielsen changes.
“What we’re pleased about is that the viewership metrics are finally capturing what we think is the accurate audience,” CBS Sports president and CEO David Berson said in response to a FOS question.
The changes are not expected to further delay the release timing of viewership data. Since last year’s arrival of Big Data + Panel, it has typically required about two days for final audience figures to arrive.
Even More Changes
The enhanced co-viewing measurement is the lead part of several Nielsen methodology changes taking effect Aug. 31. Among the other additions:
- A new machine-learning tool to check the demographic makeup of households in the Nielsen panel, and ensure that group does not improperly skew toward older residents.
- Improvements in the weighting process within Big Data + Panel.
- The inclusion of data from two government surveys to better estimate Spanish-language usage in homes. The recently concluded FIFA men’s World Cup further showed the growing market power of Spanish-language sports broadcasting in the U.S.
- Updates in how Nielsen tracks smart TV viewing.
“The work is never done, but this represents a series of really important improvements to what we’re doing,” Fuhrer said.
