Break the Chain Act This bill makes various changes related to family-sponsored immigration, such as narrowing the definition of what constitutes an immediate relative and lowering the annual numerical cap on certain classes of family-sponsored visas. A non-U.S. national (alien under federal law) who is a parent of a U.S. citizen shall not qualify for a visa for immediate relatives, which is not subject to any direct numerical limits. Currently, the spouses, unmarried children under 21, and parents of citizens are considered immediate relatives. The bill also reduces the baseline annual cap for family-sponsored visas from 480,000 to 87,934, and revises the methods for calculating the cap. Currently, the 480,000 cap may be adjusted depending on various factors but shall not be less than 226,000. A spouse or child of a sponsoring lawful permanent resident (also known as a green card holder) shall be subject to the family-sponsored visa cap. The bill revises the rules for determining whether a non-U.S. national is a child for the purposes of family-sponsored immigration, and establishes that an individual who is married or turns 25 years old prior to a visa becoming available for issuance shall not qualify as a child. The bill creates a nonimmigrant classification for non-U.S. national parents of adult U.S. citizens, which authorizes such parents for admission into the United States for an initial five-year period. Such parents shall not be authorized for employment or to receive any public benefits.