- Through can be a preposition, an adjective, and an adverb.
- Through is the only formally accepted spelling of the word.
- Thru is an alternate spelling that should be used only in informal writing or when referring to drive-throughs/drive-thrus.
Through vs. thru
Through can be used as a preposition, an adverb, and an adjective. It has several meanings, including “from one side to the other of,” “from beginning to end,” and “during an entire period”:
Through is the only acceptable way to spell the word in a formal situation. In informal situations, and especially when texting or instant messaging, the form thru is becoming increasingly popular:
There is one occasion when thru can be an acceptable choice even in formal writing. The word drive-through is commonly spelled with the shortened form of through: