Kenya Police gained promotion to the Football Kenya Federation Premier League after a 1-0 second leg victory over Vihiga United at the Utalii Grounds on Sunday.
The slim victory ensured that Police will feature in the Kenyan top flight for the first time in their history after a 2-1 aggregate triumph.
Clinton Kinanga scored the lone goal for Police in the first half, reacting fastest to a saved penalty, to add to the 1-1 stalemate last week in Mumias.
Police will be making their debut in the top-flight and join National Super League winners FC Talanta and second-placed Vihiga Bullets.
Vihiga United will now drop to the second-tier league having escaped relegation in the 2019-20 season after winning the play-off against Kisumu All Stars.
Zoo Kericho and Western Stima were the other teams that were relegated to the second tier.
Police, under the tutelage of Bob Ogolla, now prepare for their first test against the big boys with an away fixture against Kakamega Homeboyz at the Bukhungu Stadium.