Following the boyband's decision to split, the 33-year-old singer has been recording in Nashville, reported Daily Star.
"I have been given the opportunity to write my own songs. I am so excited," he said.
Filan also suggested that he is going for a country direction.
The album is due at the end of this year.
Westlife comprised of Nicky Byrne, Kian Egan, Mark Feehily and Brian McFadden besides Filan, and they split up last year after their final concert in Dublin.