The 33-year-old crooner and the 32-year-old actress were spotted together Sunday playing golf at the Lakeside Golf Club in Toluca Lake, Calif.
During their rare spotting together, Biel looked adorable in a white skirt and white shirt paired with a baseball hat and sneakers. Her man looked handsome as always in pants and a striped polo over a longsleeved white shirt.
The lovebirds walked around outside the club and Biel even stopped to check out a classic car that was parked at the valet stand.
Timberlake also took a minute on Sunday to tweet a special Father's Day message to his mom's husband. "To my Step-Father Paul: You have taught me more about life than anyone. I love you and I appreciate you more than you know #HappyFathersDay," he wrote.
Timberlake also wrote, "#HappyFathersDay everybody(that is a Dad)!!!"