The Trkmanka originates in the territory of Ždánice in the Ždánice Forest range at an elevation of 249 m (817 ft) and flows to Podivín, where it enters the Thaya River at an elevation of 152 m (499 ft).

Its drainage basin has an area of 363.3 km2 (140.3 sq mi).

[1] The average discharge at 11.2 river km in Velké Pavlovice is 0.33 m3/s (12 cu ft/s).

[2] The longest tributaries of the Trkmanka are:[3] The river flows through the municipal territories of Ždánice, Dražůvky, Želetice, Násedlovice, Terezín, Krumvíř, Kobylí, Bořetice, Velké Pavlovice, Rakvice and Podivín.

The largest of them are the fishponds Balaton and Jezero, both with an area of 4.5 ha (11 acres).