This dataset consists of very-high-resolution multibeam echosounder (MBES) bathymetry time series collected between 2009 and 2022 in two areas of the Belgian Part of the North Sea: 1) the KWGS area between the Buiten Ratel and Kwinte sandbanks (Flemish Banks) and 2) the OH-BD area along the southwestern flank of the Oosthinder sandbank (Hinder Banks). The data originate from multiple sources, including the Royal Belgian Institute of Natural Sciences, Flemish Hydrography, FPS Economy, and academic surveys, using MBES systems mainly at 300 kHz (locally 100 kHz) with 1–2 m grid resolution. The data is not available freely and can be received on request via the contacts.