Getty ImagesSix Delta credit cards are running elevated welcome bonuses through March 29, so it's your last chance to apply.
Delta Amex credit card increased offersAmex Delta credit cards give you the ability to use Delta miles in a way that non-cardholders can't.
However, Insider estimates that Delta miles are worth 1.1 cents each, on average, when booking award flights.
And if you know the best ways to use Delta miles, you can get significantly more value.
That's double the miles of the previous card bonus, which was 50,000 bonus miles and 10,000 MQMs after meeting minimum spending requirements.