Aer Lingus (United Kingdom) (EG, Belfast City) received its Air Operator's Certificate (AOC) from the United Kingdom Civil Aviation Authority (CAA) on July 9, 2021, the carrier disclosed in a filing with the US Department of Transportation.

The AOC authorises the British subsidiary of Aer Lingus (EI, Dublin International) to operate the A321-200NX(LR) and A330-300 types. The carrier recently registered its first A330, transferred from the Irish parent, and plans to take one more A330 and one A321 shortly.

Aer Lingus submitted the AOC to the US DOT with a request to expedite the granting of its foreign air carrier permit (FACP) and an exemption, and an authorisation to use the "EI" and "BA" codes of Aer Lingus and British Airways (BA, London Heathrow) on Aer Lingus (UK)'s services from Manchester International to the United States. The UK carrier plans to debut scheduled services on July 29, 2021. It will operate exclusively under the EI code and under a codeshare agreement with British Airways, a fellow member of IAG International Airlines Group.