The vehicle's front was designed by Porsche Design Group. The 13 T has six axles, and the low-floor area represents 48% of the entire vehicle floor. It is based on the Škoda 14 T. While 14 T has a front door leading to the driver's cabin only, in 13 T the front door leads to the passenger compartment.
The vehicles delivered from late 2010 differ from the preceding ones in array of passenger seats – while the initial trams have the seats in high-floor sections sideways to the driving direction (so the passengers face each other with a passage in between the lines of seats), the newer trams have the seats located in the driving direction.