The Emmy-nominated actress, 36, spoke about her relationship with her husband while on the Today show on Thursday.
Biel, who shares 3-year-old son Silas Randall with the singer, said the key to a strong marriage was hard work, and the need for commitment never goes away.
“We’re lucky enough to go and stay in different places and live in different places while we work and that’s definitely part [of having a strong marriage],” she told Savannah Guthrie, referring to her time traveling the world with Timberlake while on his tour.
“But, honestly, I just really feel like you have to work hard,” Biel shared. “That doesn’t change if you work at home or in an office or you’re on a tour. It doesn’t change, the work doesn’t change.”
The Sinner actress added, “Being devoted to the relationship is our biggest priority.”
Biel and Timberlake have been traveling around Europe recently stopping by Paris, London and Copenhagen, along with their son.
“It is fun to be on the road. You feel like a wild group of gypsies and you’re all in this together,” she told Guthrie. “You’re seeing so many new places and I think it’s amazing for our son because he’s hearing new languages. We’re talking about different countries, the names of different countries, what he likes, what he’s seen.”
“He would never have these experiences if we didn’t just get out there and go for it,” Biel added.
In April, she told PEOPLE that she’s looking forward to touring northern Europe. “I love Scandinavia, so I’m excited about Stockholm and going to Finland and Norway and all these places,” she said.
And because Timberlake “is working so hard” to deliver the best performances possible to his colossal fanbase, Biel said the best place to take date night is back to the room so the “Say Something” singer stays “healthy.”
“What he has to do and the energy output … honestly, keeping him healthy is so important. It’s not just this wild party that everybody thinks,” she continued.
Biel added, “Yes, we’re in these amazing places, but a lot of times we’re trying to protect his immunity and protect his body from breaking down. A date night for us would be just sitting in the hotel and having room service and watching a movie — just like everybody else.”