Metropolitan Daniil, whose secular name is Atanas Trendafilov Nikolov, was born in 1972 in Smolyan, Bulgaria. In 1997, he was admitted as a novice at the Hadzhidimovo Monastery, and two years later, he was ordained as a hierodeacon. In 2002, he graduated from the Faculty of Theology at the Sofia University "St. Kliment Ohridski".

In 2004, he was sent to the Rozhen Monastery and ordained as a hieromonk the same year. In 2006, he was elevated to the tank of archimandrite. Following a decision by the Holy Synod in 2008, he was consecrated as a bishop at the Patriarchal Cathedral "St. Alexander Nevsky" and appointed as vicar to the Metropolitan of Nevrokop. He held this position until 2010, when he was appointed vicar of the Metropolitan of the United States, Canada and Australia. He held this position until 2018, when he was canonically elected as the Metropolitan of Vidin.