Highly anticipated, the album surpassed all commercial expectations. It debuted at number 1 on the
Billboard Pop Albums Chart on October 8, 1976, becoming only the third album in history to achieve that feat (after British singer/composer
Elton John's albums
Captain Fantastic and the Brown Dirt Cowboy and
Rock of the Westies, both from 1975), and the first by an American artist. In
Canada, it achieved the same feat, entering the
RPM national albums chart at number one on October 16. The album spent thirteen consecutive weeks at number one in the US, eleven of which were in 1976, making it the album with the most weeks at number one during that year. During those eleven weeks,
Songs in the Key of Life managed to block four other albums from reaching the top:
Boz Scaggs’s
Silk Degrees,
Earth, Wind & Fire's
Spirit,
Led Zeppelin's
soundtrack for
The Song Remains the Same and
Rod Stewart's
A Night on the Town. On January 15, 1977, the album finally dropped to number two behind
Eagles'
Hotel California, and it fell to number four the following week, but on January 29 it returned to the top for a fourteenth and final week. By the end of its run, it had spent 35 weeks inside the top ten of the
Billboard albums chart and was on the chart for a total of 80 weeks. The album also saw longevity atop the
Billboard R&B/Black Albums chart, spending 20 non-consecutive weeks at number one. The album became the second-best selling album of 1977 in the US (behind only
Fleetwood Mac's blockbuster
Rumours), and was the highest-selling R&B/Soul album on the
Billboard Year-End chart that same year. It was certified
Diamond by the
RIAA in 2005, indicating sales of 5 million copies in the US alone (though a Diamond certification is awarded for sales of 10 million units, the RIAA counts each individual record or disc included with an album as a separate unit).
Songs in the Key of Life was also the most successful of Wonder's albums in terms of singles, the first of which, the upbeat "
I Wish", was released in November 1976, more than a month after the album was released. On January 15, 1977, the song reached number one on the
Billboard R&B chart, where it spent five weeks. Seven days after, it also reached the summit of the
Billboard Hot 100, although it spent only one week at number one. The track became an international top 10 single, and reached number five in the UK. "I Wish" became one of Wonder's standards and remains one of his most sampled songs. The follow-up single, the jazzy "
Sir Duke", was released in March 1977 and surpassed the commercial success of "I Wish". It also reached number one on the
Billboard Hot 100 (where it spent three weeks, starting on May 21) and the R&B chart (for one week, starting on May 28), but it reached number two in the UK, where it was kept from the top spot by the song "
Free" by
Deniece Williams, who provided backing vocals on Wonder's album. Released during the second half of 1977, as sales for the album began to decline, the last two singles from
Songs in the Key of Life failed to match the success of "I Wish" and "Sir Duke". "
Another Star" was released in August and reached number 32 on the Hot 100 (number 18 on the R&B chart, and number 29 in the UK), and "
As" came out two months later, peaking at number 36 on both the Pop and R&B charts. Though not released as a single, "
Isn't She Lovely" received wide radio airplay and became one of Wonder's most popular songs.
David Parton's cover of the song, recorded and released soon after Wonder's album, gave him a top 10 hit in the UK in early 1977. ==Legacy and influence==