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If you’re a Discover credit card holder and an Amazon shopper, you might be in luck. That’s because the online retailer has extended a promotion it originally launched for Prime Day, which can help you save money on many products sold by Amazon when you use cash back from select Discover cards.

Depending on which offer you’re targeted for, you can score as much as 40% off on up to $50 in purchases, while other card holders are seeing $10 off a $30 purchase or $10 off a $50 purchase.

Get as much as 40% at Amazon, up to a $20 discount, with your Discover credit card.
Amazon
Get as much as 40% at Amazon, up to a $20 discount, with your Discover credit card.

If you’re eligible for any of these offers, you’ll need to use Discover cash back to pay for at least a portion of your Amazon purchase at checkout to trigger the discount before the promotion expires. The offers were originally slated to end after Prime Day, but they’ve now been extended to June 30. And if you previously saw one version of the offer, you might now be targeted for a different version.

But there are a number of steps you need to follow first to actually lock in the savings from any of these offers, so we’ve put together a step-by-step guide to ensure you’re getting every penny.

How to save up to 40% at Amazon with your Discover card

For starters, in order to potentially be targeted for this promotion, you must have a Discover credit card. These include the Discover it® Cash Back, the Discover it® Miles and the Discover it® Chrome.

If you have one of these cards but haven’t connected your Discover card to your Amazon account, you’ll need to link your two accounts. Log in to Amazon and add your Discover card as a payment method, then look for the option to enroll in “Shop with Points” under the “Your Account” tab (or click here to get to Shop with Points). On the next screen, click the “Enroll” button for the Discover card you just added.

Add your Discover credit card to your Amazon account and enroll in "Shop with Points."
Amazon
Add your Discover credit card to your Amazon account and enroll in "Shop with Points."

Once your accounts are linked, you’ll need to click here to check if you’re eligible for an offer. Since these are targeted promotions, you might see a message saying that you’re not eligible, even if you have a Discover card connected to your Amazon account. But if you just enrolled in “Shop with Points,” you may need to wait 24 hours for Amazon’s records to refresh before being able to see an offer.

Related: Lower your expenses by getting one of these credit cards with no annual fee.

If you’re eligible, make sure to activate your offer by clicking on the “Activate promotion” button. You can then shop at Amazon as you normally would, but during the checkout process, you’ll want to select your linked Discover card as your payment method.

You’ll then need to apply at least 1 Discover cash back point to pay for your purchase to trigger the discount. Amazon might automatically default to applying points for the full purchase amount, but you can manually change it and designate the amount of cash back you want to apply toward your purchase — as little as 1 cent if you want. The rest can then be paid for with your Discover card.

You only need to apply 1 Discover cash back point to your Amazon order to get the discount.
Amazon
You only need to apply 1 Discover cash back point to your Amazon order to get the discount.

Fortunately, you’ll get the same value when redeeming your Discover cash back at Amazon as you’d receive if you chose a statement credit redemption instead. Basically, $1 in cash back equals $1 at Amazon, which means you’re getting the same 1 cent per point. This is a much better value than what you’d receive when using American Express or Chase points, who often run similar Amazon promotions for their own card members.

Related: Save money at Amazon with targeted American Express cards.

Once you’ve applied at least 1 point to your payment, you’ll see the discount added to your order, but keep in mind you’ll only see the discount on items sold directly by Amazon, not most third-party sellers.

With the 40% off offer, the discount will apply on every order you place through June 30 until you hit a total of $20 in savings. But for the other offers, you’ll need to place a single order with the minimum purchase amount to see the savings appear.

Up to 40% off third-party retailer gift cards too

While these Discover discounts don’t apply to Amazon gift cards, they do apply to many other third-party retailer gift cards that Amazon sells. And Amazon literally has hundreds of options, including retailers that might be useful right now such as Netflix, DoorDash, Safeway and more.

Take $30 off your grocery bill by buying a gift card to Whole Foods and applying this Discover offer.
Amazon
Take $30 off your grocery bill by buying a gift card to Whole Foods and applying this Discover offer.

So even if you don’t have anything you need at Amazon at the moment, you can buy a gift card for yourself using the discount and bank the savings for later. You can even pair these promotions with many of Amazon’s daily deals or any of its other money-saving offers, like saving $20 when you spend $60 on select beauty products.

Related: Pay off your debt faster with these balance transfer credit cards.

What should you do if you’re not targeted?

If you’re not targeted for any of these particular Discover promotions, keep checking back, as sometimes previously ineligible customers are suddenly eligible. Similar offers also resurface throughout the year, both for Discover cards and other credit cards from Chase, Citibank, Capital One and American Express, so there’s a chance you’ll be able to save at another point down the line.

And if you don’t have any of these credit cards, make sure you check out our guide to be sure you’re using the best credit card for Amazon purchases, even if you can’t get any discounts right now.

With Amazon being a go-to shopping site for many households, this promotion is the perfect way to save money if you’re eligible. So make sure you take a look if you’re a Discover credit card holder, and if you’re targeted, get your discount when you buy from Amazon!

Check out CNN Underscored’s list of the 26 of the coolest home essentials at Amazon under $100.

Find all the latest personal finance deals, news and advice at CNN Underscored Money.