Capital One miles to Japan Airlines Mileage Bank, 30 percent bonus
Capital One to Japan Airlines Mileage BankWhat is happening
Between September 1 and September 30, 2026, Capital One is adding a 30 percent bonus on transfers to Japan Airlines Mileage Bank.
The bonus is not really a bonus
Capital One normally transfers to Japan Airlines at four to three, so 1,000 Capital One miles become 750 Japan Airlines miles. You lose a quarter of them on the way. The 30 percent bonus brings 1,000 up to 975, which is almost back to even. So this is less a sale and more the ratio finally being fair.
The rule people miss
Japan Airlines Mileage Bank only lets you redeem miles for yourself and for family members you are related to by blood or by marriage. If you were planning to book a friend, this program will not let you. Read that before you transfer, because it is one way.
What it is actually good for
Japan Airlines opens award seats 360 days out, right when the schedule loads, which is genuinely useful if you are trying to get business class to Japan on a specific date. It also has a distance based chart for partner airlines with some real value in it.
The real ratio
Expires: September 30, 2026. Transfers are one way. Confirm the bonus in your own Capital One account and read the Mileage Bank family rules before you move anything.