Earn more United miles with the MileagePlus X app

United Airlines’ MileagePlus X app is a valuable, easy-to-use tool for United flyers. It allows you to earn bonus United miles in a few different ways, but my favorite is by purchasing gift cards through the app. Here’s how it works.

Related: United Airlines MileagePlus: Guide to earning and redeeming miles, elite status and more

The MileagePlus X app offers e-gift cards from over 270 merchants, ranging from restaurants to retailers.

To get started, download the app, enter your United MileagePlus information and tap the yellow “Buy eGift cards” button.

Under the “Catalog” tab, you can scroll through merchants by category or see what merchants are offering extra miles. If you’re looking for a specific merchant, choose “All” and use the search box.

Once you’ve found your merchant, click “Continue to pay now.” The next screen will tell you the minimum and maximum amounts for your gift card. You can enter any number within these limits — down to the penny — and the app will show how many miles you’ll earn.

In my experience, e-gift cards become available within minutes of purchasing them. Once I decide to buy something, I can purchase a gift card for the amount I need and use it right away.

You can find all your gift cards under the “Purchases” tab. Click on one to get the barcode to scan in-store or the number and PIN to enter when shopping online. You can then mark it as redeemed to remove it from your list.

Miles earned through MileagePlus X typically post within a day or two. You can see your earnings under the “Transactions” tab.

I’ve found the MileagePlus X app surprisingly easy to use, and it’s a huge benefit for in-store shopping or online retailers that aren’t available on shopping portals.

If your retailer is on a shopping portal and MileagePlus X, you could stack the rewards. For instance, at the time of writing, MileagePlus X was offering 5 miles per dollar spent on Adidas purchases, while MileagePlus Shopping was offering 3 miles per dollar spent at Adidas — so you could earn a total of 8 United miles per dollar by shopping online through the portal and paying with a MileagePlus X e-gift card.

That’s not including the rewards you’ll earn on the credit card you use to purchase your gift card. MileagePlus X purchases typically code as the merchant (rather than United), so you should choose your payment method based on the merchant’s category. For instance, you could use one of the best cards for dining to buy a gift card to a restaurant, or purchase an Airbnb gift card with a card that earns bonus points on travel.

Bottom line

United’s MileagePlus X app is a fast and easy way to earn bonus miles. Plus, you can earn 25% more miles on e-gift cards if you hold a United Chase card — even if you don’t pay with that card.

If you’re considering adding a United card to your wallet, the following cards are offering elevated welcome bonuses through Jan. 29:

• United Gateway℠ Card: Earn 30,000 bonus miles after you spend $1,000 on purchases in the first three months your account is open.
• United℠ Explorer Card: Earn 60,000 bonus miles after you spend $3,000 on purchases in the first three months your account is open.
• United Quest℠ Card: Earn 70,000 bonus miles plus 500 Premier qualifying points after you spend $4,000 on purchases in the first three months your account is open.
• United Club℠ Infinite Card: Earn 90,000 bonus miles after you spend $5,000 on purchases in the first three months your account is open. You can also earn an additional 5,000 bonus miles after you add an authorized user to your account in the first three months your account is open.

Related: 4 reasons someone in your family needs a United credit card