The Scottish Fire and Rescue Service control room in Dundee will now take emergency calls from Inverness.
Staff in the City of Discovery already handle calls from the north-east following the closure of the Aberdeen control room last month.
They are now tasked with receiving alerts from across the Highlands and Islands after the northern base shut.
In 2014, the fire service agreed the closure of five control rooms across the country, cutting the number of centres down to three. Dundee, Edinburgh and Renfrewshire remain open.
Work is under way to build a new state-of-the-art command unit next to the city’s Macalpine Road fire station to cope with the increased demand. Work on that is set for completion in March 2017.