Regional Ocean Partnership Act of 2021 This bill allows the National Oceanic and Atmospheric Administration (NOAA) to designate and support Regional Ocean Partnerships between coastal states that share a common ocean or coastal area. Specifically, NOAA may designate a partnership as a Regional Ocean Partnership if it (1) is established to coordinate the interstate management of coastal resources; (2) focuses on the environmental issues affecting the ocean and coastal areas of the coastal states participating in the partnership; (3) complements existing state coastal and ocean management efforts on an interstate scale, focusing on shared regional priorities; (4) does not have a regulatory function; and (5) is not duplicative of an existing Regional Ocean Partnership. The bill designates the following entities as Regional Ocean Partnerships: the Gulf of Mexico Alliance, the Northeast Regional Ocean Council, the Mid-Atlantic Regional Council on the Ocean, and the West Coast Ocean Alliance. Each partnership must maintain mechanisms for consultation and engagement with the federal government, tribal governments, and nongovernmental entities, such as academic organizations. A partnership may use provided federal funds to award grants and enter into contracts for certain purposes, including to monitor the water quality and living resources of multistate ocean and coastal ecosystems.