2003–04 Serie C1

The 2003–04 Serie C1 was the twenty-sixth edition of Serie C1, the third highest league in the Italian football league system.

Semifinal

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Play-out

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Final Verdict
Arezzo and Cesena promoted to Serie B

Varese, Pavia and Prato relegated to Serie C2

Repechage : Pavia and Prato admitted at Serie C1 2004–05

Semifinal

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Play-out

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Final Verdict
Catanzaro and Crotone promoted to Serie B

L'Aquila, Paternò, Taranto and Viterbese relegated to Serie C2

Team failed
Varese, L'Aquila, Paternò, Viterbese