The line runs from the northwest of the canton of Zürich from Winterthur and heads for Schaffhausen.
At both terminal stations, connections to InterCity and InterRegio trains as well as other S-Bahn services exist.
S33 services are operated by RABe 511 units, except for weekday services to Schaffhausen which are run by Re 450 class locomotives pushing or pulling double-deck passenger carriages.
Between 2010 and 2018, the S33 services were operated by THURBO rolling stock (Stadler GTW units).
Media related to S33 line (Zürich S-Bahn) at Wikimedia Commons