To evaluate the current microplastics (MPs) contamination on the NW coast of Portugal, opportunistic samples from coastal areas with different levels of anthropogenic impacts were analyzed. Water samples were collected from a coastal marine protected area, an urban estuary, a submarine wreck, and a recreational marina. An optimized protocol for the quantification of MPs, followed by visual identification and FTIR spectroscopy analysis was used to characterize MPs (polymer, type, size, color). MPs were found in all the case studies. A total of 2456 ​MPs particles were identified and classified as fibers (39%), film (39%), and fragments (22%). Up to 54% of MPs had a size range between 1 and 3 ​mm. Transparent was the dominant color (56%), followed by white (19%). Polyethylene and polypropylene were the main MPs polymers detected. Higher MPs concentration were found in areas associated with high intense fishing and shipping activities. This study showed that different types of MPs were present in all the aquatic environments surveyed, mainly in areas with more anthropogenic activities, emphasizing the need for measures to properly manage plastic litter and mitigate marine plastic pollution.