News of the milestone comes as Spotify continues a fund-raising from investors in advance of a launch in the US.
The Anglo-Swedish company has 6.67 million users, the majority of whom use a free service subsidised by adverts.
Spotify's profitability depends on users switching to premium services that remove adverts and allow listeners to use smartphones.
The company announced on its website's blog: "It seems like only yesterday we were hatching ideas for a new music service in a tiny office-cum-apartment with a broken coffee machine.
"So it's with a sense of real pride and excitement that we can announce a new milestone today, having welcomed our millionth paying subscriber to the service. "
Spotify is in the process of a $100m funding round that analysts estimate values the company at $1bn (Â£616m).
The company's plans to launch in the US have been delayed by concerns at the big music labels about the success of its business model.
Spotify pays royalties each time a song is played on its service.
Last year, it was estimated that the subscriber base represented about 7%-8% of Spotify's total user base.
But with one million subscribers, that percentage has risen to about 15%, the company said.
Online music service Spotify has announced that it now has one million paying subscribers across Europe.