What was the Four Tops' first single to reach #1 on the U.S. charts?

The Four Tops' first single to reach #1 on the U.S. charts was "I Can't Help Myself (Sugar Pie, Honey Bunch)" in June 1965. After their first success, the Four Tops released a long series of successful hit singles. Among the first wave of these hits were the Top 10 "It's the Same Old Song" (1965), "Something About You" (1965), "Shake Me, Wake Me (When It's Over)" (1966), and "Loving You Is Sweeter Than Ever" (1966). Music pundits liked to note that the Four Tops records often represented the epitome of the Motown Sound: simple, distinctive melodies and rhymes, and call-and-response lyrics. Also, the musical contributions of studio band, the Funk Brothers helped to make them particularly noteworthy.

The song 'I Can't Help Myself (Sugar Pie Honey Bunch)' was a 1960s hit song that was recorded by the Four Tops for the Motown label. It was written and produced by Motown's main production team Holland–Dozier–Holland. The song was one of the most well-known Motown recordings and was a among the decade's biggest hits.

The single 'I Can't Help Myself' reached number one on Billboard's R&B chart and also peaked at number one on the Hot 100 for two non-consecutive weeks, from June 12 to June 19 and from June 26 to July 3 in 1965. It replaced the very popular 'Back in My Arms Again' by The Supremes another well known group from Motown.