I Am... Sasha Fierce made its first debut at number five on Japan's Oricon international albums chart and subsequently moved to the top spot on the chart.[128] The album debuted at number one on the US Billboard 200, selling 482,000 units in its first week and giving Knowles her third consecutive number one album in the US.[129] Eventually, Knowles became the third female artist of the 2000s decade to have her first three albums debut at the top spot of the US Billboard 200 albums chart.[130] Having sold 1,459,000 copies in 6 weeks of release in 2008 alone,[131] I Am... Sasha Fierce emerged as the tenth best selling album of 2008 according to Billboard magazine.[132] With this achievement, Knowles eventually equaled Garth Brooks, Mariah Carey, and Shania Twain for placing an album in Nielsen SoundScan's year-end top 10 for the fifth time.[133] The album later emerged as the second best selling album of 2009 in the US itself.[134] It has been certified double platinum by the Recording Industry Association of America (RIAA).[135] As of April 2011, the album has sold around 2.9 million copies in the United States according to Nielsen SoundScan.[136] In the United Kingdom, the album debuted at number ten on November 29, 2008, becoming Knowles' lowest-debuting album despite having higher first week sales than her previous album, B'Day.[137] Following Knowles' performance at the 2008 The X Factor finale with winner Alexandra Burke, the album moved up to number nine on December 27, 2008.[138] Due to the success of its singles in the United Kingdom and especially due to the success of "Sweet Dreams", I Am... Sasha Fierce rose from number five to its highest peak of number two in its thirty-ninth week on the chart, which was the week of August 16, 2009.[139]

Knowles performing "Single Ladies (Put a Ring on It)" in Berlin on the I Am... Tour, 2009
In Ireland, I Am... Sasha Fierce debuted at number three,[140] making it Knowles' second top three album in that country. It would later go to top the Irish charts for two consecutive weeks in early January 2009,[141][142] giving Knowles her second Irish number-one album.[143] In Australia, I Am... Sasha Fierce debuted at number nine in late November 2008[144] and peaked at number eight in early January 2009.[145] Following the success of singles "Sweet Dreams" and "Broken-Hearted Girl", the album rebounded to a new peak of three on two separate occasions in October 2009 and it was certified triple-platinum on November 23, 2009.[146] In New Zealand, the album debuted at number 16 in late November 2008[147] and initially peaked at number six in early March 2009.[148] After growing popularity of its singles, especially "Sweet Dreams", the album upped to a new peak of three on September 21, 2009.[149] The album was certified platinum on April 26, 2009, (after twenty-three weeks on the chart) shipping over 15,000 copies to retailers.[150] In Spain, the album debuted and peaked at number 7 on November 26, 2008,[151] and was certified platinum for shipment of over 60,000 copies on October 26, 2009.[152] The album went on to be certified diamond in Brazil.[153] After the 52nd Grammy Awards ceremony, I Am... Sasha Fierce either ascended several albums charts or re-entered others and set new peaks in countries such as Switzerland, Austria, and Portugal in February 2010.[154][155][156] After having peaked at number five on the Polish Albums Chart on February 8, 2009,[157] I Am... Sasha Fierce re-entered the chart at number one on August 28, 2011, that is nearly three years after its release in Poland.[158] As of March 2011, the album has sold over seven million copies worldwide.[159]