The nearby Blue Lagoon luxury geothermal spa immediately shut its doors, as it did during previous eruptions.
“We have evacuated and temporarily closed all our operational units,” the operator said on its website.
“We will remain closed through Sunday, March 17. Further updates and information will be provided here as they become available,” it added.
Iceland has more than 30 active volcanoes, making the north European island a prime destination for volcano tourism – a niche segment that attracts thousands of thrill seekers.
The site of the eruption was between Hagafell and Stora-Skogfell, the same area as the previous outbreak on February 8, the Met Office said.
In 2010, ash clouds from eruptions at the Eyafjallajokull volcano in the south of Iceland spread over large parts of Europe, grounding about 100,000 flights and forcing hundreds of Icelanders to evacuate their homes.