Navy Uniform Regulations does not require Sailors to have military creases in our uniforms. If you prefer a sharper look while in uniform then military creases are authorized. Some uniform shirts sold at our Navy Exchanges have permanent military creases “glued” into the fabric. However, sewn-in creases are not authorized.
Reference: U.S. Navy Uniform Regulations, Chapter Two, Section 1, Article 2101.3.f.