A bachelor's degree (from Middle Latin baccalaureus) or baccalaureate (from Modern Latin baccalaureatus) is an undergraduate academic degree awarded by colleges and universities upon completion of a course of study lasting three to six years (depending on institution and academic discipline). The two most common bachelor's degrees are the Bachelor of Arts (BA) and the Bachelor of Science (BS or BSc). In some institutions and educational systems, certain bachelor's degrees can only be taken as graduate or postgraduate educations after a first degree has been completed, although more commonly the successful completion of a bachelor's degree is a prerequisite for further courses such as a master's or a doctorate.

In countries with qualifications frameworks, bachelor's degrees are normally one of the major levels in the framework (sometimes two levels where non-honours and honours bachelor's degrees are considered separately). However, some qualifications titled bachelor's degree may be at other levels (e.g., MBBS) and some qualifications with non-bachelor's titles may be classified as bachelor's degrees (e.g. the Scottish MA and Canadian MD).

The term bachelor in the 12th century referred to a knight bachelor, who was too young or poor to gather vassals under his own banner. By the end of the 13th century, it was also used by junior members of guilds or universities. By folk etymology or wordplay, the word baccalaureus came to be associated with bacca lauri ("laurel berry") in reference to laurels being awarded for academic success or honours.

Under the British system, and those influenced by it, undergraduate academic degrees are differentiated between honours degrees (sometimes denoted by the addition of "(Hons)" after the degree abbreviation) and non-honours degrees (known variously as pass degrees, ordinary degrees or general degrees). An honours degree generally requires a higher academic standard than a pass degree, and in some systems an additional year of study beyond the non-honours bachelor's. Some countries, such as Australia, New Zealand, South Africa and Canada, have a postgraduate "bachelor with honours" degree. This may be taken as a consecutive academic degree, continuing on from the completion of a bachelor's degree program in the same field, or as part of an integrated honours program. Programs like these typically require completion of a full year-long research thesis project.