During World War II, as they commissioned and fleeted in, the 175 2,100-tonners were organized into nineteen squadrons (21–25 and 45–58), each with two divisions. Normally, a squadron was commanded by a captain who also commanded a division—commonly the lower-numbered one. Division composition could change rapidly, however, and divisions did not always operate together.

Initial or intended (e.g., where a ship was damaged before its squadron was formed) organization and initial or usual flagships were as follows:

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The first five 2,100-tonners from Bath and the first four from Federal.

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The second four ships from Federal and from Bath plus one from Charleston Navy Yard originally fitted with a floatplane catapult.

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The first four ships from Orange, four more from Bath plus a second from Charleston Navy Yard intended for a floatplane catapult.

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Three of the first four ships from Bethlehem, Staten Island (two high-bridge and one low-bridge), the last of four high-bridge ships from Puget Sound Navy Yard, the first four ships from Bethlehem, San Francisco (all low-bridge) and the last high-bridge ship from Boston Navy Yard (initially held for a floatplane catapult).

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The second four ships from Orange, the third four from Federal (three high-bridge; one low-bridge) and the third ship from Charleston Navy Yard (intended for a floatplane catapult).

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The first four ships from Boston Navy Yard and four from Bath plus one from Puget Sound Navy Yard that initially carried a floatplane catapult.

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