The amphipod crustacean Talitrus saltator, an established biomonitor of trace metal bioavailabilities in coastal waters, was used to investigate the spatial distributions of Al, Cu, Fe, Mn, Sr, and Zn across 14 sites covering the distributional range of the species in the Baltic Sea. Cluster analysis and PCA of bioaccumulated metal concentrations did not identify any particular region as a metal hotspot, but they clearly showed variations in the geographical distributions of metal bioavailabilities. In spite of higher salinity, western regions of the Baltic experienced higher bioavailabilities of metals than the eastern part. There were also noticeable differences between metal bioavailabilities of the regions influenced by the discharges of the Odra and the Vistula rivers. It was also possible to discern two groups of metals influencing the similarities among sites. One of them consisted of Al, Cu, Fe, and Sr, while the other of Mn and Zn. The results exemplified the usefulness of T. saltator as a convenient biomonitoring species in identifying areas of different trace metal bioavailabilities to nearshore coastal biota.