QS

QS is a code for:
* Smart Wings, IATA airline designator
* Travel Service (Czech Republic), IATA airline designator

QS is an abbreviation for any of the following:
* Quacquarelli Symonds, an education and careers networking company
* Quality start, a baseball statistic calculated for starting pitchers
* Quantity surveyor
* Queen's Scout
* Queen's Serjeant, an obsolete legal position in the United Kingdom
* Quicksort
* Quality System (QS) Regulation
* Quorum sensing
* Québec Solidaire
* Quadratic Sieve
* Quis separabit?, a Loyalist motto