Aberystwyth-based tour operator, Tango Tours, ceased trading as an Atol holder on Wednesday (March 16).
A statement from the Civil Aviation Authority said the company traded under the names Teithiau Tango and Tango Tours and websites www.tangotours.co.uk and www.teithiautango.co.uk.
The CAA added: “We are currently collating information from the company and will update this page as soon as possible.”
Tango Tours specialised in tours to Latin America and Antarctica.
Its sister brand, Teithiau Tango, offered group tours to Welsh-Patagonia.