Northumberland-based specialist Tangent Expeditions has ceased trading.
The Civil Aviation Authority said the company, which traded under the websites tangent-expeditions.co.uk, greenlandexpeditions.com and icemanpolar.com closed down on 30 September.
The CAA said it is currently updating information about the company, which it said held an ATOL up until 31 March 2021.
On its website, the company describes itself as ‘the world’s leading Greenland expedition specialist and logistics consultants’.
Bookings and payments made after 30 April 2021 are not ATOL-protected, the CAA says.