The 12th IAAF World Half Marathon Championships was held on October 4, 2003 in Vilamoura, Portugal.

A total of 171 athletes, 98 men and 73 women, from 49 countries took part.

[3][4] Complete results were published[5] for the men's race,[6][7] for the women's race,[8][9] for men's team,[10][11] and for women's team.

The participation of 171 athletes (98 men/73 women) from 49 countries is reported.

[5] Although announced, athletes from  Cameroon and  Republic of the Congo did not show.