Umkomaas, a small coastal town on the subtropical south coast of KwaZulu-Natal, South Africa was formed when a harbour was built in 1861 to export sugar. The town rests beside the mouth of the navigable uMkhomazi River, also known as the Mkhomazi or Umkomaas. With the successful dredging of Durban harbour's sandbar and arrival of the railway, like Port Shepstone, the harbour fell into disuse, but the town came to life.

A large number of whales once used the estuary as a nursery, giving birth in the shallows. The Zulus named the river after this spectacle (uMkhomazi means the place of cow whales). The settlement was originally known as South Barrow, with its suburb known today as Ilfracombe then called North Barrow.

The town is located 48 km south of central Durban and is accessible by rail and by roads including the N2 Freeway and the coastal R102 or "Old Main Road."

The South African Navy mine countermeasures vessel SAS Umkomaas is named in honour of the river and town.