Since colonial times, substantial regional income disparities have been reported for Indonesia. However, in spite of a wide variety of available data and indicators, so far published data on Indonesian per capita GDP in colonial times are limited to macro-estimates for the entire archipelago or are confined either to Java or to the Outer Islands. In this paper we provide a first attempt to arrive at estimates of diverging income and living standards at a regional level. We implement the Geary and Stark method on a large body of data collected by the colonial government, to estimate GDP for ten macro-regions and five benchmark years between 1870 and 1930. Our findings, corrected for prices, confirm the image arising from the existing literature of major divergences within the Indonesian archipelago in general, and of a higher per capita GDP in most of the Outer Islands (all islands of the Indonesian archipelago except for Java and Madura) compared with Java in particular. This was definitely the case in 1870 and still the case in 1920, but the picture is less clear for 1930, which was the final year before Indonesia’s commodity exports started to collapse.