Music vision
The Finnish firm's NSeries phones can accept a range of digital music formats including both MP3 and Apple's and Windows' preferred formats - although some music may not work because of download restrictions.
Nokia has sold 15 million music-enabled phones over the past three months, illustrating the trend for people to use their phones to access entertainment products.
It sold 45 million such phones last year, and expects sales to top 80 million in 2006.
"People should be able to access all the music they want, anywhere, anytime and at a reasonable cost," said Anssi Vanjoki, an executive vice president at Nokia.
"With this acquisition, we aim to deliver that vision and a comprehensive music experience to Nokia device owners during 2007."
The deal, which much be approved by Loudeye shareholders, is expected to be completed towards the end of the year.
Seattle-based Loudeye employs about 130 staff in five countries.
In addition to its music catalogue, Loudeye provides the technology for digital media platforms through which content can be sold.
"This agreement recognizes the key role that Loudeye and our people play in the digital mobile music market and reflects the power of our products," said Loudeye chief executive Michael Brochu.