"Therefore I Am" debuted at number 94 on the US Billboard Hot 100 with 3.1 million streams, 5,000 downloads, and 11.7 million radio airplay audience impressions in its first four days of tracking. The song rose to number two on the chart the next week after it drew 24.2 million streams, 14,000 downloads, and 18.3 million radio airplay audience impressions, giving Eilish her fourth top-10 hit in the United States and 20th total Hot 100 hit. With a vault of 92 positions, "Therefore I Am" made the fourth-greatest leap in the Hot 100's history. The song also peaked within the top five on the US Billboard airplay Hot Rock & Alternative Songs chart, and topped the Mainstream Top 40 chart, her second number one on the latter chart. It reached number two in Canada and received a platinum certification by Music Canada (MC) for track-equivalent sales of 80,000 units.
