Burglary is generally the unlawful entry of a building or structure to commit a felony criminal offense (crime), theft, or assault. The definition of burglary varies from state to state (and in the federal system), and some states have different degrees of severity of the burglary offense, depending on the nature of the unlawful entry (type of building or structure), the intended purpose, and the illegal action taken by the defendant once inside the building or structure. In some states, breaking into an automobile, a coin-operated machine, or an ATM (automated teller machine) with the intent to commit a theft may also constitute the crime of burglary.

A defendant generally commits the offense of burglary of a building or habitation (1) by entering a private habitation or any part of a building that was not open to the public, (2) without the consent of the owner, and (3) with the intent to commit a felony, theft, or assault.

A defendant may also commit the offense of burglary of a building or habitation by entering with consent, but remaining hidden with the intent to commit a felony, theft, or assault—or entering with consent and attempting to commit a felony, theft, or assault, or actually committing a felony, theft, or assault.

Some states make a distinction between burglary of a habitation (a place used for overnight accommodations) and burglary of a building that is not a habitation (home). Burglary of a habitation is usually treated as a more serious offense with greater penalties.

In New Mexico, burglary is defined under NM Stat § 30-16-3 (2021) as the unauthorized entry into any dwelling or structure with the intent to commit any felony or theft therein. New Mexico law distinguishes between different types of burglary based on the nature of the structure entered: residential burglary (also known as burglary of a dwelling), commercial burglary, and auto burglary. Residential burglary is considered a third-degree felony, while commercial burglary is a fourth-degree felony, and auto burglary is a fourth-degree felony as well. The severity of the offense and the penalties increase if the burglary involves a dwelling because it is considered a violation of the personal living space, which is treated with greater sanctity. The intent to commit a felony, theft, or assault is a crucial element of the crime, and the defendant does not need to actually complete the intended crime to be charged with burglary. The law also covers situations where a person lawfully enters a building but then remains concealed or commits a felony, theft, or assault without the owner's consent.