On the week ending November 29, 2008, "White Horse" debuted and peaked at number thirteen on the Billboard Hot 100. Its appearance, along with six other songs, on the chart tied Swift with Hannah Montana (Miley Cyrus) for the female act to have the most songs charting on the Billboard Hot 100 in the same week,[20] a record later surpassed by Swift herself when she charted eleven songs at once in 2010.[21] The following week, the song dropped to number fifty-six,[22] and, on the week ending April 25, 2009, it spent its last week on the Billboard Hot 100 at number forty-four, after a total of twenty-two weeks on the chart.[23][24] The song is one of thirteen songs from Fearless charted within the top forty of the Billboard Hot 100, breaking the record for the most top forty entries from a single album.[25] The single was certified platinum by the Recording Industry Association of America for shipments exceeding one million copies.[26] As of November 2017, "White Horse" has sold 2 million copies in the United States.[27]

The single debuted at number thirty-seven on Billboard Hot Country Songs on the week-ending December 12, 2008. It jumped at number twenty-six on the following week, the biggest jump of the week.[28] On the week ending February 14, 2009, it entered the top ten at number ten, scoring Swift's seventh consecutive top ten hit on the chart.[29] It peaked at number two on the week-ending April 4, 2009 and held there on the following week before dropping at number seven.[30][31][32] It charted for a total of twenty weeks on Billboard Hot Country Songs.

"White Horse" debuted at number twenty-seven in Canada on the week ending November 29, 2008.[33] On the week ending January 24, 2009, "White Horse" peaked at number forty-three in Canada.[34] It was certified gold by Music Canada for sales of 40,000 digital downloads.[35] In Australia, the track entered at its peak at number forty-one on the week ending February 22, 2009.[36] In United Kingdom, "White Horse" debuted and peaked at number sixty on the week ending March 21, 2009. It stayed on United Kingdom for two weeks.[37]