The Sanctuary is comprised of six distinct units, forming a network of marine protected areas around the islands of the Territory of American Samoa. Tables containing the exact coordinates of each point described below can be found in Appendix to Subpart J—National Marine Sanctuary of American Samoa Boundary Coordinates. The total areal estimate of the six units combined is 10,255 nmi 2 (13,581 sq. mi.).

(a) Fagatele Bay Unit. The Fagatele Bay unit is a coastal embayment formed by a collapsed volcanic crater on the island of Tutuila, Territory of American Samoa, and includes Fagatele Bay in its entirety. The landward boundary is defined by the mean high high water line of Fagatele Bay until the point at which it intersects the seaward boundary of the Sanctuary as defined by a straight line between Fagatele Point (−14.36527, −170.76932) and Steps Point (−14.37291, −170.76056) from the point at which it intersects the mean high high water line seaward.

(b) Fagalua/Fogama'a Unit. The landward boundary of the Fagalua/Fogama'a Unit is defined by the mean higher high water line of Fagalua/Fogama'a until the point at which it intersects the seaward boundary of the Fagalua/Fogama'a Unit as defined by a straight line between Steps Point (−14.37307, −170.75852) and Sail Rock Point (−14.36534, −170.74119) from the point at which it intersects the mean higher high water line seaward.

(c) Aunu'u Unit. The Aunu'u Unit is comprised of two adjacent zones.

(1) Zone A. The Aunu'u Unit boundary for Zone A is defined by the coordinates provided in Table 1 and the following textual description. The Zone A boundary extends from Point 1, the northwest corner of the unit, southward to Point 2 along a straight line following the western boundary of the unit, which is aligned with Taugamalama Point on Tutuila. It then extends northeastward in a multi-part line along the deepest seaward edge of Nafanua Bank from Point 2 to Point 3 and then to Point 4, which lies on the southern boundary of Zone B. The boundary then follows a straight line westward towards Point 5 until it intersects the mean higher high water line at the southern tip of Ma'ama'a Cove. The landward boundary of Zone A is defined by the mean higher high water line from this intersection point at the southern tip of Ma'ama'a Cove to the intersection of the mean higher high water line and the straight line between Point 6 and Point 7 at Salevatia Point. From this intersection point at Salevatia Point, the boundary extends straight west to Point 7, which has the exact same coordinates as Point 1.

(2) Zone B. The Aunu'u Unit boundary for Zone B is defined by the coordinates provided in Table 2 and the following textual description. The Zone B boundary extends from Point 1, the northeast corner of the unit, southward along a straight line following the eastern boundary of the unit to Point 2, which is on the southern boundary of the unit. The southern boundary then follows a line westward towards Point 3 until it intersects the mean higher high water line at the southern tip of Ma'ama'a Cove Point. The landward boundary of Zone B is defined by the mean higher high water line from this intersection point at the southern tip of Ma'ama'a Cove around the volcanic crater to the intersection of the mean higher high water line and the straight line between Point 4 and Point 5. From here, the boundary extends seaward straight north to Point 5. The northern border, the last straight line, is defined by connecting Point 5 and Point 6, along the northern boundary of the unit, which is aligned with Matuli Point on Tutuila. Point 6 has the exact same coordinates at Point 1.

(d) Swains Island Unit. The Swains Island Unit boundary is defined by the coordinates in Table 3 and the following textual description. The seaward boundary of the Swains Island Unit approximates the three nautical mile territorial sea boundary from the mean higher high water line (shoreline) of the island. The seaward boundary begins south of the island at Point 1 and continues initially to the west in sequential order clockwise around the island to Point 33. The landward boundary of the Swains Island Unit is the mean higher high water line and begins on the northern shoreline of the island and follows the shoreline counterclockwise initially to the west until it intersects the line segment between Point 34 and 35. From this intersection the boundary continues offshore to the northwest to Point 35 and then to Point 36 and Point 37. From Point 37 the boundary continues east-northeast towards Point 38 until it intersects the shoreline. From this intersection the boundary follows the shoreline southeast around the southernmost part of the island and then to the northeast until it intersects the line segment between Point 39 and Point 40. From this intersection the boundary continues offshore to the southeast to Point 40 and then to the northeast to Point 41. From Point 41 the boundary continues to the northwest towards Point 42 until it intersects the shoreline. From this intersection the boundary follows the shoreline initially to the northeast around the island counterclockwise and then to the northwest back to where it began on the northern shoreline.

(e) Muliāva Unit. The Muliāva Unit boundary is defined by the coordinates provided in Table 4 and the following textual description. The landward boundary of the Muliāva Unit is the extreme low water line, which adjoins the boundary of the Rose Atoll National Wildlife Refuge. The Muliāva Unit seaward boundary extends from Point 1, the southwest corner of the unit, to Point 2 along a straight line northward following the western boundary of the unit. From Point 2, the line extends in a straight line westward to Point 3. It then extends along a straight line northward to Point 4. From Point 4, the line extends in a straight line eastward to Point 5. From Point 5, the line extends along a straight line northward to Point 6. It then extends along a straight line eastward from Point 6 to Point 7, which is on the eastern boundary of the unit. The boundary then follows a straight line southward until it intersects the line of the southern boundary of the unit at Point 8, the southeastern corner of the unit. The last straight line is defined by connecting Point 8 and Point 9, which has the exact same coordinates as Point 1, along the southern boundary of the unit.

(f) Ta'u Unit. The Ta'u Unit boundary is defined by the coordinates provided in Table 5 and the following textual description. The Ta'u Unit boundary extends from Point 1, Vaita Point, along the mean higher high water line southward along the western coast to Point 2, Si'ufa'alele Point. From Point 2, the boundary extends offshore 0.25 miles to Point 3 to become conterminous with the offshore boundary of the National Park of American Samoa. From Point 3 the boundary continues to follow the coastline 0.25 miles offshore until it reaches Point 4, which is directly south of Si'u Point. From Point 4, the boundary extends due south to Point 5. From Point 5, the boundary extends due west to Point 6, forming the southern border of the unit. From Point 6, the boundary extends due north until it reaches Point 7, directly west and one mile offshore from Point 8, which is Point 1, also known as Vaita Point.