Who managed the longest period between their first ever release & their first number 1 single?
Louis Armstrong made his first recording as bandleader in 1925. His single Hello Dolly reached number 1 in 1964.
Looks like, in the US it was Santana with 'smooth':
The record for the longest wait from an artist's Hot 100 debut entry to its first #1 belongs to Santana, with 30 years between the time he first cracked the Hot 100 with "Jingo" (October 25, 1969) and the first of 12 weeks at #1 with "Smooth," featuring Rob Thomas (October 23, 1999).
In the UK I couldn't find that stats for that but the longest between number 1's is The Hollies at 23 years:
The Hollies went 23 years between their first top hit "I'm Alive" in 1965 and their next top hit, the re-release of "He Ain't Heavy, He's My Brother" in 1988. They had eleven other singles in the top 10 in that interim time, including three singles to reach the number 2 spot.
1Beats the one I had in mind - Elton John, who's first [solo] number 1 in the UK was Sacrifice, 1990, 22 years after his first release. I'll give it a couple of days before hitting the 'tick' just in case anyone finds a surprise.– TetsujinMay 23, 2015 at 11:54
A bit outside the requirements (single -> #1), but you can maybe consider anyway :
"Sugar Man" by Sixto Rodriguez
This song wasn't released as a single but was part of an album in 1970... and didn't really reach number 1 in 2012, but I think almost everyone heard it then on the radio/tv!
You can see why by watching the movie Searching for Sugar Man (I can't sum it up... it would spoil the movie & that fascinating story)
In 2022 we have to add Kate Bush to this list.
First UK hit 1978 with Wuthering Heights.
Running Up That Hill, first released in 1985, eventually made the top slot in 2022, due to its popularity gained from the TV show Stranger Things.
That makes 44 years.
Oh, I just realised it doesn't count, because Wuthering Heights also went to No 1. I'll leave this here as an honorable mention.