Eastern Airways is permanently halting its flights between Stornoway and Aberdeen.
The airline confirmed it is withdrawing from the route this month, with the last day of service coming on October 29.
An Eastern Airways spokesperson said: “Regrettably, due to the increasing costs of operating the Aberdeen – Stornoway route, we are left with no alternative but to withdraw the service from October 29, 2018, as it becomes unviable to sustain.
“With a mix of increasing ground handling charges at Stornoway airport, fuel increasing, compensation likelihood as we head into winter combined with a shortage of aircraft following ground handling damage sustained to two aircraft in the past months reducing fleet availability in the short-medium term, these have combined to culminate in our decision to withdraw from the route.
“Passengers with bookings beyond October 29 will be offered a full refund.”
The service is vital to Lewis islanders employed in the oil and gas sector and travel to the city for work..
In May, Eastern Airways reduced the flights to just one daily service after two months of operating two return services a day.
Reliability was poor with many flights disrupted and cancelled.
At the time, Eastern Airways admitted reliability fell short.