By Colin Kellaher

DispatchHealth, which provides on-demand medical services to patients in their homes, on Tuesday said it raised $135.8 million in a Series C funding round led by Optum Ventures, the independent venture fund of UnitedHealth Group Inc.'s Optum.

The Denver startup's valuation wasn't disclosed, but a representative said the round brings DispatchHealth's total funding to $216.8 million.

Existing investors Alta Partners, Questa Capital and Echo Health Ventures also participated in the round, along with new investors Oak HC/FT and Humana Inc.

DispatchHealth said its services provide high-acuity, lower-cost medical care for patients with high medical and social needs. The company said the additional funding enables DispatchHealth to grow in existing markets, expand to new markets and to launch additional services.

Write to Colin Kellaher at colin.kellaher@wsj.com

Corrections and Amplifications

This article was corrected on June 25, 2020 because it stated that the valuation of startup DispatchHealth was disclosed in conjunction with its Series C funding round. It wasn't disclosed.