untill

Untill is generally considered a nonstandard or historical spelling of the English word until. In contemporary writing, the standard forms are until and, in some contexts, till. Untill is usually regarded as a misspelling or an archaic variant that should be avoided in modern English.

Until and till are used to indicate up to a point in time or up to the occurrence of an event. Until is the more formal and widely accepted form in both American and British English. Till is an integrated synonym that is shorter and can feel more informal; it also exists as a separate noun meaning a cash register in some contexts. Because of this dual meaning, til is sometimes used as a contraction in poetry or casual writing, but untill should not be used in place of either until or till.

Historically, English has included various spellings for this sense, and you may encounter untill in older texts or in dialect writing. However, modern style guides and dictionaries do not treat untill as standard. When editing or composing contemporary English, prefer until, or till where appropriate for a more informal tone.

Examples: We stayed until midnight. We waited till dawn. We waited until the bus arrived; untill would be considered incorrect in formal prose.