We estimated the life expectancy for 2003 for 23 provinces in the Islamic Republic of Iran using population and mortality data from the Ministry of Health and Medical Education. The underreporting of deaths above 4 years was corrected using the Brass Growth Balance method. We assumed that the distributions of population, deaths, and hence life expectancy in the 23 provinces were equal to those for all 28 provinces of the country. Thus we estimated life expectancy at birth to be 71.56 years for the total population [95% uncertainty interval (UI): 71.52-71.62]; 70.09 (95% UI: 70.02-70.16) years for males, and 73.17 (95% UI: 73.10-73.24) years for females. Our estimates were higher than the model-based estimates of the Statistical Centre of Iran, United Nations agencies and the World Bank, due to differences in the estimation methods used.