United Airlines just dropped a new way to earn MileagePlus miles: a debit card! Issued by Sunrise Banks, the United MileagePlus Debit Rewards Card gives you 1 mile for every $1 spent on United purchases and 1 mile for every $2 spent on everything else. Plus, there's a signup bonus of 10,000 miles after you spend $500 in the first 4 months. This is good news if you are trying to rack up United miles, and especially useful if you are debit-only! But here's the catch: it comes with a $4 monthly fee (waived if you keep a $2,000 average monthly balance). They also dangle extra miles based on how much money you keep in your account, but honestly, with current interest rates, you're probably better off putting your savings elsewhere. There's also a yearly spending bonus of 2,500 miles if you spend $10,000 in debit purchases. So, is it worth it? If you're strictly a debit card user and want to earn United miles on everyday spending, it could be a decent option, especially with the sign-up bonus. Also, for some purchases (think paying your taxes or something similar) you may be able to earn miles without the fees typically associated with credit cards. But for most of us award travelers, a good rewards credit card will likely offer better earning rates and more valuable perks. The jury's still out on whether you can hold this card alongside the Southwest and Wyndham debit cards, and what happens if you cancel and re-apply down the road, but it definitely adds another option to the miles-and-points game.