The following is the 2003–04 network television schedule for the six major English language commercial broadcast networks in the United States. The schedule covers primetime hours from September 2003 through August 2004. The schedule is followed by a list per network of returning series, new series, and series cancelled after the 2002–03 season. All times are Eastern and Pacific, with certain exceptions, such as Monday Night Football. New series are highlighted in bold. Each of the 30 highest-rated shows is listed with its rank and rating as determined by Nielsen Media Research. Other Legend PBS is not included; member stations have local flexibility over most of their schedules and broadcast times for network shows may vary. Also not included are stations affiliated with Pax TV, as its schedule is composed mainly of syndicated reruns although it also carried a limited schedule of first-run programs. The 2003–2004 season marked the final time that the major networks scheduled substantial original scripted drama series on Saturdays. After years of declining ratings on that particular evening, beginning with the 2004–2005 season the networks ceased scheduling original dramas on Saturdays, choosing instead to fill the schedule with non-fiction programming and reruns. From August 13 to 29, 2004, all of NBC's primetime programming was preempted in favor of coverage of the 2004 Summer Olympics.

Sunday

NOTE: On Fox, The Ortegas was supposed to air at 8:30-9, but it was cancelled.

Monday

Tuesday

NOTE: On The WB, Fearless was supposed to have started in the Fall at 9–10, but it was delayed to midseason, then it was cancelled both due to production difficulties.

Wednesday

Thursday

NOTE: On Fox, The O.C. was supposed to air at 9-10 after Tru Calling, but at the last minute stick with repeats.

Friday

Saturday

By network

ABC

Returning series New series Not returning from 2002-03

CBS

Returning series New series Not returning from 2002-03

Fox

Returning series: New series: Not returning from 2002-03:

NBC

Returning series: New series: Not returning from 2002-03:

UPN

Returning series New series Not returning from 2002-03

The WB

Returning series New series Not returning from 2002-03 Note: The * indicates that the program was introduced in midseason.

Renewals and cancellations

Renewals

ABC

CBS

Fox

NBC

UPN

The WB

Cancellations/series endings

ABC

CBS

Fox

NBC

UPN

The WB