I don't often see "till" in American texts. American English more often uses "until". I think "till" is more usual in British English. - my opinion
Originally Posted by Unregistered
They have the same meaning.
In spoken American English "until" is often reduced to 'til. I would say it is debatable as to whether AE speakers are saying till or 'til - short for "until". I believe they are thinking "until" and saying 'til. Therefore, I would say they are using a reduction of "unitl".
Also, I would suggest not using 'till in formal writing. I would use "until".
Usage Note: Till and until are generally interchangeable in both writing and speech, though as the first word in a sentence until is usually preferred: Until you get that paper written, don't even think about going to the movies. ·Till is actually the older word, with until having been formed by the addition to it of the prefix un-, meaning “up to.” In the 18th century the spelling 'till became fashionable, as if till were a shortened form of until. Although 'till is now nonstandard, 'til is sometimes used in this way and is considered acceptable, though it is etymologically incorrect.