A couple of years ago, British Airways Executive Club switched award charts and introduced a new, distance-based award chart which has its ups and downs. Firstly, let’s note the chart below (First class isn’t included and generally I wouldn’t recommend redeeming Avios for First Class since only the long haul flights have First Class).
Firstly, British Airways does charge fuel surcharges/taxes & fees on most airlines that you can redeem your Avios on. The only exceptions are (where there are either no fuel surcharges or very low fuel surcharges): American Airlines (flights within the United States, Mexico, Canada, Caribbean, Central and South America), Alaska Airlines, most LAN Airlines flights, Aer Lingus, airberlin, British Airways flights within Europe (and South Africa on their partner airline), domestic Qantas flights, and S7 flights.
Avios are incredibly useful for redeeming on short-haul flights. A flight that is under 650 miles costs just 4.5k Avios whereas a domestic U.S. flight around that range varies from $150+ USD. So in general a flight that is under 2.000 miles is probably best booked using Avios since flights that are 2.001 or more miles start at 12.5k Avios – which is similar to most domestic U.S. airlines’ mileage requirements. Business class costs twice what Economy costs, which is usually the case in most mileage programmes.
For 10.000 avios, you can fly up to 2.000 miles, so for example, you can easily fly from Los Angeles to Chicago using Avios… whereas the typical flight on that route sometimes might cost much more money than a regular domestic flight.
Since I currently live in Seattle, I use Avios for travel on Alaska Airlines and since they have a ton of west coast routes, I can practically fly anywhere in the west coast for 7.5k Avios one-way in Economy (its not like Alaska Airlines has a great First Class product anyway).
For flights that are longer than 2k miles… well you personally have to decide and compare to your ‘native’ programme to see if you can use Avios to save money or miles. In general, it doesn’t make sense to redeem Avios for long-haul flights because of the distance-based award chart and because of fuel surcharges.
To conclude, Avios are a very valuable point currency if used for short-haul flights. The awesome thing is that British Airways partners with Starwood Preferred Guest, Chase Ultimate Rewards and American Express Membership Rewards so it is very easy to earn Avios through multiple credit cards.