in Love with You" reached the top 20, peaking at #14. It became her second top 20 hit in that country. The song also reached #2 on the Canadian RPM singles chart, her highest peak at the time. The song stayed on the chart for 20 weeks. In Australia, the single debuted at #30 on the ARIA Charts, during the week of 25 June 2000. Five weeks later, it reached #10, marking her second Australian top-10 song. The single stayed on the chart for 15 weeks. It was later certified gold by the Australian Recording Industry Association (ARIA), denoting shipments of 35,000 units within the country. In New Zealand, the song debuted at #33 on the issue of 6 August 2000. In its third week on the chart, the single peaked at #20. In the United Kingdom, "I Think I'm in Love with You" debuted at #15 on the UK Singles Chart in the week of 15 July 2000, remaining on the chart for seven further weeks. It became her second British top-20 single. In Switzerland, the single debuted at #61 on the issue dated 25 June 2000. The following week, it peaked at #41 and stayed on the chart for 12 weeks. The single peaked at #3 on the Ultratip chart of Belgian Wallonia, and #36 on the Belgian Flanders Ultratop 50 chart. It also reached #30 in Italy. "I Think I'm in Love with You" peaked at #31 on the European Hot 100 Singles chart, as compiled by Billboard. Music video "I Think I'm in Love with You" was the first of Simpson's videos to be set to an up-tempo beat. The video was directed by Nigel Dick. The video starts out with Jessica and her girlfriends, including her sister, Ashlee running into a group of factory workers unloading furniture from a truck. The workers join Simpson and her girlfriends in an impromptu dance on the streets. The video is also intercut with scenes of Simpson in front of a giant heart. The video's TRL world premiere debut was on June 1, 2000, at number 10. The video peaked at number five and stayed on the countdown for 25 days, making it her first successful video on MTV's TRL. Live performances "I Think I'm in Love with You" was included on the set list of the Heat It Up Tour (1999), DreamChaser Tour (2001) and Reality Tour (2004).