Eid al-Fitr, also called Breaking the Fast Feast, the Sugar Feast, Bayram (Bajram), the Sweet Festival or Hari Raya Puasa and the Lesser Eid, is an important religious holiday celebrated by Muslims worldwide that marks the end of Ramadan, the Islamic holy month of fasting (sawm). The religious Eid is a single day during which Muslims are not permitted to fast. The holiday celebrates the conclusion of the 29 or 30 days of dawn-to-sunset fasting during the entire month of Ramadan. The day of Eid, therefore, falls on the first day of the month of Shawwal. The date for the start of any lunar Hijri month varies based on the observation of new moon by local religious authorities, so the exact day of celebration varies by locality. However, in most countries, it is generally celebrated on the same day as Saudi Arabia.
Source: wikipedia.org
In 2016 Eid al-Fitr in USA falls on July 7.