US citizens and Lawful Permanent Residents (referred to as LPRs or green card holders) can petition for certain family members and relatives. US citizens can petition for the following relatives; spouses, children, parents, and siblings. Green card holders (LPRs) can petition for the following relatives: spouses and children.

For immediate family members of US citizens (spouses, children under 21 years of age, and parents), there is no wait times for visa availability. This category is called immediate relatives.

For all other family petitions, there are sometimes lengthy waiting times for visa availability, due to strict annual limits on green card numbers. The length of the wait depends upon the family preference category and the country of origin. Their category is called preference relatives.