"I Knew I Loved You" is a single by Austrailian pop duo Savage Garden from their album Affirmation. It was their second number one after "Truly Madly Deeply" and reached the top spot of Hot 100 on the week dated January 29, 2000, staying there for three consecutive weeks. After its third week at number one, the single was knocked off by Mariah Carey's "Thank God I Found You" featuring Joe and 98 Degrees and then returned to the top again the following week for its fourth and final week at the top. The song peaked at #10 in the UK Singles Chart in November 1999.

The music video was filmed with director Kevin Bray in August 1999 on a New York City Subway set that had previously been used for Seinfeld.

It features the band in a subway station with Hayes playing out a romantic plot on the subway with Kirsten Dunst as the object of his affections. The video shows the band alone in a carriage and also full of people. Then the train seems to stop and the power goes out, a red back up light comes on and everyone in the carriage joins hand. Hayes who is sitting opposite Dunst reaches out his hands to her. As they touch, we are shown the couple walking through a park bathed in sunlight, laughing and holding hands. Then it's back to reality as the train lights come back on and comes to the next station. Both Hayes and Dunst get up to leave, looking at each other as they exit the carriage and part ways. The video ends with Savage Garden performing by themselves in the carriage and subway.