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We describe the fabrication and operation of vertically emitting distributed feedback quantum cascade ring lasers operating in the terahertz frequency range. A twofold increase in radiation efficiency is observed as compared to Fabry–Pérot lasers. The emitters exhibit a robust single-mode operation around 3.2 THz with a side mode suppression ratio higher than 30 dB. Modal and threshold characteristics are investigated by performing finite element simulations with results in good agreement with experiments. The ring-shaped resonator facilitates beam collimation which results in a symmetric far-field profile.