If you have an American Express Membership Rewards account, you can transfer points to participating frequent travel programs. You can transfer your points to one of three loyalty programs that use Avios as their currency. These three programs are British Airways Executive Club account, Aer Lingus AerClub and Iberia Plus. Usually one Membership Rewards point equals one Avios. So 1,000 American Express Membership Rewards points will yield 1,000 Avios.
However, now through 9/30/2024, you can receive 30% more Avios when you transfer Membership Rewards points one of these programs. So during this offer, 1,000 American Express Membership Rewards points will yield 1,300 Avios.
If you are trying to accumulate Avios right now, this may be something you may want to consider taking advantage of.