Höfðavatn (Icelandic pronunciation: [ˈhœvðaˌvahtn̥] ^ⓘ) is a lagoon-like lake in northern Iceland. It is located in the municipality of Skagafjörður.

Höfðavatn lies at the fjord of Skagafjörður about 7 km north of the village of Hofsós.

The surface of the Höfðavatn is about 10 km²; the maximum depth is 6.4 m, the middle depth 3.9 M.^[1] North of the lake lies the Málmeyjarsund [ˈmaulmˌeiːjarˌsʏnt], west of Þórðarhöfði [ˈθourðarˌhœvðɪ].^{[citation needed]}