The one-online-class rule, explained

Short answer: no more than one class or three credits of online coursework per term can count toward your full course of study — and if you're down to a single final class, it can't be online at all. 8 CFR 214.2(f)(6)(i)(G)

The rule counts toward the minimum, not against your schedule

This is the piece that unlocks most confusion: the limit applies to the credits that satisfy your full course of study requirement — typically 12 undergraduate or 9 graduate credits. Online classes beyond that minimum are your business. Concretely, for an undergraduate needing 12 credits:

• 9 in-person + 3 online = 12 counted credits. Compliant.
• 6 in-person + 6 online = 9 counted credits (only one online class counts). Out of status.
• 12 in-person + 6 online = 12 counted credits plus electives. Compliant — the extra online classes never enter the math.

What "online" means here

The regulation reaches classes that don't require your physical attendance for classes, exams, or other purposes integral to completing the class. A hybrid course with required in-person sessions generally counts as in-person; a course that's technically "on campus" but never requires you in a room generally doesn't. The registrar's course coding usually decides how your school reports it — when your reading of a syllabus and the code disagree, that's a DSO conversation before enrollment, not after.

Why this rule gets students in trouble quietly

Nothing errors out when you register. The schedule looks full, the tuition bill is real, and SEVIS registration happens at the start of term — the mismatch surfaces later, when someone audits what counted. By then you've spent a semester below a full course of study without knowing it. The five-minute prevention: before each registration, count only your in-person credits plus one online class, and check that number against your program's full-time minimum.