The 2003–04 NBL season was the 26th season of competition since its establishment in 1979. A total of 12 teams contested the league. This season marked the first NBL season that featured the New Zealand Breakers, the first New Zealand team in the Australian competition. Also, the Canberra Cannons were replaced by the Hunter Pirates.

Regular season

The 2003–04 regular season took place over 22 rounds between 1 October 2003 and 29 February 2004.

Round 1

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Round 2

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Round 3

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Round 4

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Round 5

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Round 6

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Round 7

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Round 8

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Round 9

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Round 10

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Round 11

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Round 12

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Round 13

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Round 14

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Round 15

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Round 16

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Round 17

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Round 18

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Round 19

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Round 20

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Round 21

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Round 22

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Ladder

The NBL tie-breaker system as outlined in the NBL Rules and Regulations states that in the case of an identical win–loss record, the results in games played between the teams will determine order of seeding. ''1West Sydney Razorbacks won Head-to-Head (2-1). ''

Finals

Playoff bracket

Elimination Finals

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Semi-finals

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Grand Final

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All Star Game

Most Valuable Player

Awards

Player of the month

Coach of the month

All NBL Team