Brendan Coyle was born in Corby, Northamptonshire to an Irish father and Scottish mother; his parents moved to Corby from County Tyrone, Ireland. Brendan holds Irish citizenship and has previously lived in Dublin and London. However, according to a video clip from the site for "Rockface" he resides in Norfolk.

Brendan is also the great nephew of footballing (i.e. soccer) legend Sir Matt Busby of Manchester United fame.

Brendan trained at drama school in Dublin, founded in the late 1960s as the Focus Theatre, was co-founded by his aunt Mary Elizabeth Burke-Kennedy. Brendan started there in 1981 and then received a scholarship to Mountview Theatre School in England in 1983. He has directed at least two plays at Mountview since graduating from there.

Brendan has done a number of stage, television, and movie productions, including the play "The Weir" for which he won an Olivier Award for Best Supporting Performance award for his part as the bartender, Brendan. He continues to work on stage, in film and on television.