ABBA's last world-wide #1 was "One of Us" (1981), which hit #1 in at least four countries. It only reached #2 in the UK though there are some who believe it probably reached #1 the next week but there was no chart published (due to Christmas holidays). "One of Us" reached #33 in the US. The last British #1 was Super Trouper (1980). In the US, ABBA's last (and only) #1 on the Hot 100 was Dancing Queen (1976) but "The Winner Takes it All" peaked at #1 on the Adult Contemporary chart in 1980 and "Super Trouper" reached #1 on the Dance chart in 1981.
1983. Their last original single, "Under Attack", reached #1 in several countries.
Abba's first-ever #1 single was "He Is Your Brother". It reached #1 on the Swedish radio play chart in 1972. The first Abba single to reach number 1 outside Sweden was "Ring Ring" (1973), which hit #1 in Belgium. "Waterloo" was Abba's third chart-topper and the first to reach #1 in an English-speaking country.
Super Trouper, 1980.
The Visitors.
See the link below for the full list of Abba single releases.
Depends what you consider to be a hit. ABBA's first chart single in the UK was Waterloo, which peaked at #1 in 1974. Their next release was "Ring Ring", which was actually a remix of a 1973 single. The 1974 version reached #32 in the UK. Their next single, "So Long" only reached #91. But in 1975, "I Do, I Do, I Do, I Do, I Do" cracked the top 40, peaking at #38. Their next top 10 was "S.O.S.", which reached #6. ABBA's next single was their second #1 hit in the UK, "Mamma Mia".
ABBA recorded for the last time as a group in 1983.
I believe that ABBA's last really big hit was The Winner Takes It All.
If you're thinking of Abba, as a single it reached No 2 in South Africa and No 33 in UK. But as a track on ABBAs Greatest Hits and ABBA The Movie it hit No 1 all over the world.
People Need Love.
Super Trouper.
There is no single answer for this question. ABBA had many songs that millions around the world loved.