Download these 4 shopping portal buttons to amplify your earnings

If you frequently shop online, it's worth learning how to maximize online shopping portals. After all, online shopping portals are a great way to earn extra points and miles for your next trip.

To find the highest-earning online shopping portal for a purchase, you can use a shopping portal aggregator. But, if you want to focus on earning rewards with one specific loyalty program -- perhaps American Airlines, if you're looking to earn Loyalty Point-eligible AAdvantage miles through shopping -- you may want to install a shopping portal browser extension.

Best of all, there's currently a promotion that may encourage you to install and use one or more shopping portal extensions.

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When you install the shopping button in your browser and use it to make a purchase over $25 by March 26 at 11:59 p.m. Eastern time, you can earn 1,000 bonus miles with the following four programs (follow the links below to install each program's shopping portal button in your browser):

• American AAdvantage eShopping
• United MileagePlus Shopping
• Southwest Rapid Rewards
• Delta SkyMiles Shopping

You must keep the button installed for at least 30 days after March 26. So, you'll need to keep the button installed until at least April 26, 2022. And, you won't be eligible for bonus miles if you'd installed the button at any point before March 21, 2022. In short, the bonus miles are for new users of each program's shopping button.

Of the four airlines, 1,000 miles is worth the most with AAdvantage ($17.70 based on TPG's valuations). The 1,000 bonus AAdvantage miles won't be Loyalty Points-eligible miles. But the miles you earn on purchases will be Loyalty Point-eligible. That's right: using the AAdvantage eShopping portal can help you qualify for AAdvantage elite status. And best of all, you may be able to stack promotions to earn even more rewards.

For example, Levi's is running a promotion on the American AAdvantage eShopping portal where you can earn 5 miles per dollar instead of the standard 2 miles per dollar.

And on my Hilton Honors American Express Aspire Card, I'm currently targeted for an Amex offer that gives me $30 off a purchase of $150 with Levi's.

The information for the Hilton Aspire card has been collected independently by The Points Guy. The card details on this page have not been reviewed or provided by the card issuer.

By using my Hilton Aspire card for the $150 purchase with Levi's, I could earn as follows:

• $30 statement credit for using the targeted Amex offer (worth $30).
• 1,000 American AAdvantage bonus miles (worth $17.70).
• 750 American AAdvantage miles (5 miles per dollar spent, worth $13.28 and 2.5% of the Loyalty Points I'd need for AAdvantage Gold status).
• 450 Hilton Honors points (3 points per dollar spent, worth $2.70).

I could net $63.68 of savings plus 750 Loyalty Points on a $150 purchase with Levi's. Of course, read the Amex Offer terms carefully before you try to stack offers, as some Amex Offers require you to click through a specific link.

But, as you can see, online shopping portals can help you snag extra rewards on your online purchases. And thanks to this current promotion, you can earn 1,000 bonus miles with four different airline programs by simply installing their shopping portal button, making an eligible purchase and keeping the button installed through April 26.