What date did Congress adopt the first United States flag design?

Congress adopted the first United States flag design on June 14, 1777.

The Second Continental Congress passed the Flag Resolution during the Revolutionary War. It specified thirteen alternating red and white stripes and thirteen white stars on a blue field, representing the thirteen states. The resolution did not prescribe the stars’ arrangement, their exact shape, or the proportions of the flag.

The wording said the stars should form a new constellation. That phrase allowed later designs to vary, including circular and irregular arrangements. The familiar 50-star flag is therefore the result of later additions and design choices rather than a complete blueprint from 1777.

The first flag resolution is commemorated annually in the United States on Flag Day, June 14. The resolution itself did not officially name a designer. The popular Betsy Ross story is a later tradition and is not established by surviving contemporary government records.