I don’t write about a lot of mileage purchase offers, because they usually aren’t a good deal. Even with a bonus of 85% or 100% the points still frequently cost more than they’re worth.
One exception to the rule on why I don’t cover too many airline mileage sales is this one from Air Canada Aeroplan: up to 110% bonus on purchased miles, no tax for U.S. residents, and a favorable exchange rate. That brings the mileage cost down to $0.0124 per point. I value Aeroplan miles at 1.4 cents apiece.