Heathrow Rewards allows you to collect points on your spend at Heathrow airport. These points can then be converted into Avios, Etihad Guest, Miles & More or Virgin Flying Club miles at a 1:1 ratio.
If you’re not already a member, join/register here before 20 April 2015 and you’ll receive an initial 100 free points, plus a further 1000 points when you spend £25 in a single day at Heathrow (again, before 20 April).
Note that while this is a BA promo, you do not need to convert the points to Avios, although that obviously is an option.
In terms of ongoing earning, you basically earn 1 point per £1 spent at Heathrow, and can convert to miles in units of 250. Occasionally, there will be conversion bonuses, so it is worth waiting for one of these before you convert.
Note that Heathrow Rewards members also get double free Wi-Fi at Heathrow (8 hours rather than 4).
If you are after more free air miles and hotel points, don’t forget to visit our Free Miles/Points page, here.