The 2003 Campeonato Nacional Apertura Copa Banco del Estado was the 73rd Chilean League top flight tournament, in which Cobreloa won its sixth league title after eight years.
Qualifying stage
Scores
Group standings
Group A
Group B
Group C
Group D
Aggregate table
Repechaje
Santiago Wanderers qualify to playoffs as best placed team despite having drawn with Unión San Felipe.
Playoffs
First round
Colo-Colo and Huachipato qualified as best losers.
Knockout stage
Finals
Top goalscorers
Pre-Copa Sudamericana 2003 Tournament
All sixteen first level teams took part in this tournament, plus -and only for this edition-, all sixteen second level teams took part as well. One of the qualified teams to the Copa Sudamericana coming from this division, Provincial Osorno.