Whereas ABBA Gold pulls together 19 of the group's biggest hits and most familiar songs, Number Ones is a variation on this concept, collecting 18 tracks that were #1 hits in many of the countries where ABBA were successful. In the end, only three tracks from ABBA Gold do not make the cut: "Does Your Mother Know", "Lay All Your Love on Me", and "Thank You for the Music".

In the UK, the track list includes the full length version of "Summer Night City" (originally released on the Thank You for the Music box set) and an additional track "Ring Ring", which, oddly enough, was never a big hit in that territory.

A limited edition, also released in the UK, includes a bonus disc with 12 tracks from ABBA's #1 albums.

In Taiwan, a hidden track follows "I Have a Dream". This hidden track, titled "ABBA Remix" and running for 3:31, is a medley of the choruses of the 18 songs on the CD.

^*sales figures based on certification alone
^{^}shipments figures based on certification alone

UK Gold, 100,000

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