ABSTRACT This article asks what the impact is of ownership concentration and deconcentration on editorial cross-media selfpromotion. Zooming in on two significant ownership changes in the small and highly concentrated media market of Flanders (Belgium) in 2017-18, we quantitatively analysed 1,209 articles published in the two largest Flemish newspapers comparing periods before and after two significant moments of ownership concentration and deconcentration. We assess the immediate impact of these changes on cross-media self-promotion between newspapers and audio-visual channels in terms of frequency, length, and presence of visual cues in referencing to media brands belonging to the same mother company and brands that belong to the rival commercial media company. We also measure references to the public broadcaster as a control variable to check whether changes before and after mergers, and/or differences between newspapers from both media groups might be explained by factors other than ownership changes. Our analysis reveals that concentration in Flemish media ownership led to significantly more coverage of the "own" brands of the newspaper’s overarching company. We discuss the broader implications of our Flemish findings, with the two most dominant private media corporations rapidly expanding their brand portfolios in several European countries.