Only If

"A only if B" means B is required for A. It translates to "If A, then B." The part after "only if" is the necessary condition, which is the opposite of what most people expect.

Example

"You can vote only if you are registered" means "If you voted, you are registered."

See also

• Conditional Statement
• Contrapositive
• Necessary vs. Sufficient Conditions

Back to the full glossary

Last updated October 12, 2026