"Hasta Mañana" (Spanish for "Until tomorrow"), which originally was titled "Who's Gonna Love You?", is the fourth track on Swedish pop group ABBA's second studio album, Waterloo.

Initially fearing that "Waterloo" might be too risky to enter for the 1974 Eurovision Song Contest, the group considered performing the ballad "Hasta Mañana" instead, as they thought that it was more in style with previous Eurovision winners. Eventually, they decided on "Waterloo", primarily because it featured Agnetha Fältskog and Anni-Frid Lyngstad sharing lead vocals, whereas "Hasta Mañana" had Fältskog as the sole lead vocalist. ABBA believed that this would give the wrong impression of them to the world.

While the song was being recorded, they decided to give up on it at one point because none of them could sing it properly. Agnetha alone was in the studio and decided to play around with it. She felt if she could sing it in a Connie Francis style it would work — and it did.

In Australia, "Hasta Mañana" was later used as a B-side on the "So Long" single (which never charted). After being featured in the immensely popular The Best of ABBA TV Special, broadcast in March 1976, the song became a Top 20 hit in Australia and Top 10 hit in New Zealand.

It reached number 2 on the charts in South Africa, where it remains immensely popular to this day.

In some countries this song was released as a single from their Waterloo album.

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