Note that you do earn Tier Points on Aer Lingus and LATAM flights as well, despite them not being alliance members. For details, the two photos below are examples of the Tier Points and Avios you'll earn on a flight from London to Singapore and from London to New Delhi.

Yes, you can earn British Airways (BA) Executive Club Tier Points on Aer Lingus, but only if you book the flight as a codeshare with a BA flight number (e.g., flight BA6010 operated by Aer Lingus). If you book directly through Aer Lingus with an "EI" flight number, you will generally only earn Avios (points), but not Tier Points, unless you are traveling on a specific "Select" or "Flex" fare on a route between London and Ireland. In 2026, despite both airlines being owned by International Airlines Group (IAG), Aer Lingus is still not a full member of the oneworld alliance, which complicates the reciprocal status benefits. However, for those with BA Silver or Gold status, flying on Aer Lingus provides perks like lounge access and priority boarding on many routes, regardless of how the ticket was booked. To maximize your "Tier Point run," always ensure your booking confirmation shows a "BA" prefix. If you have already flown and didn't receive your points, you can use the "Claim Missing Avios" tool on the BA website, but be prepared for a denial if the flight didn't have that crucial BA code.