Most American Express card members typically think of their Amex points as opportunities for amazing travel opportunities. While that’s true, there’s another lesser-known use for them — redeeming them for purchases at Amazon. And Amazon is back at it again with a terrific promotion where you can actually save money by using your Amex points this way.

Right now, targeted American Express card members can save as much as 40% on their next Amazon purchase, for up to $50 in savings when you use Amex points to pay for at least a portion of your purchase at checkout through May 1, 2022. Other card members are getting 20% off for up to $40 in savings, or $10 off a $100 purchase.

While this is a targeted offer, it appears to be fairly widely available to eligible American Express card members, although scoring the deal can be a little complicated. But we’re going to take you through it step by step to make sure you’re getting as much of a discount as possible when you’re shopping at Amazon.

To start, you must have an American Express card that earns Membership Rewards points. Amex cards that earn other types of rewards, such as cash back or airline miles, won’t work. But there are plenty of Amex cards that earn Membership Rewards points — a small sampling of them is at the end of this story.

Next, you’ll need to link your Amazon and American Express accounts. Add your American Express card as a payment method in your Amazon account, if you haven’t already. Then look for the option to enroll in “Shop with Points” under the “Your Account” tab, and click the “Enroll” button for the Amex card you just added.

Once your accounts are connected, you’ll need to activate the offer by clicking on this link. Remember, this is a targeted promotion, so not everyone will be eligible for it — you could be targeted for any one of the offers or none of them. When you click on the link, if you see a message that you’re not eligible, then you’re unfortunately not targeted for this particular promotion.

But even if you’re not targeted, don’t give up hope. If you just enrolled in “Shop with Points,” you may need to wait 24 hours for Amazon’s records to refresh before knowing if you’re targeted, so check back in a day or so.

If you’re eligible, activate the offer by clicking on the “Activate now” button — the enrollment page will indicate your particular discount. You can then shop at Amazon as you normally would, though only products sold and shipped by Amazon are eligible for these discounts. Additionally, Amazon gift cards are excluded, though other third-party retailer gift cards sold by Amazon are eligible.

But wait! There’s one more step. When you’re ready to check out, you’ll want to make sure to select your linked American Express card as your payment method. Then you’ll need to use at least 1 point to pay for your purchase for the discount to apply.

When paying with Amex Membership Rewards points at Amazon, 1 point equals 0.7 cents. That’s not the best value you can get for Amex points. Frequent flyer website The Points Guy values Membership Rewards points as high as 2 cents each when redeemed for travel.

However, it’s important to note that you don’t have to pay for your entire Amazon purchase with points to get these discounts. In fact, you can use just 1 point and pay for the rest with your Amex card, and you’ll still see the discount applied to your order.

To pay with the minimum number of points required, enter $0.01 in the points section at checkout, which will apply just 1 point to your payment, You can use any number of points you want, but if you don’t make this change, Amazon may automatically apply the maximum number of points to cover the entire purchase, so you’ll want to make sure to update the amount before you place the order.

Once you’ve applied at least 1 point to your payment, you’ll see the discount added to your order. For the 20% or 40% offers, the discount will apply on every order you place through May 1 until you hit a total of $40 in maximum savings on the 20% offer, or the $50 maximum on the 40% offer. For the $10 off $100 offer, you’ll need to spend a minimum of $100 in a single transaction between now and May 1 to see the savings.

Let’s take a look at some examples of how you can apply this discount to your upcoming Amazon purchases, even if you don’t need anything from Amazon right at the moment.

If you’re in the market for new travel accessories, the Rockland Double Handle Rolling Backpack is one of our choices for 22 of our favorite travel backpacks to consider before your next trip. This backpack with wheels currently prices at $80 before taxes and shipping, but if you apply the 40% Amex discount, that price drops to a much cheaper $48.

Or, if you’re hoping to pick up a pair of Apple AirPods, right now Amazon has them at a relatively standard $179.99. But if you’re targeted for the Amex 40% off discount, you can knock a full $50 off the price and get them for just $129.99 before taxes and shipping.

And even though these discount offers don’t apply to Amazon gift cards, they do apply to many other  retailer gift cards that Amazon sells. Amazon has literally hundreds of options, including retailers that might be useful right now, such as Netflix, DoorDash, Whole Foods and more. So even if you don’t have anything to get at Amazon before May 1, you can always buy a gift card for yourself using the discount and bank the savings for later.

Plus, you can 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.

Even if you aren’t eligible for any of these particular Amex promotions, offers like this typically resurface many times throughout the year, so keep on checking back. Amazon is also currently running a similar promotion for Discover card holders — check out CNN Underscored’s guide to that promotion for all the details.

You might also find that even if you aren’t eligible now for one of these offers, you could magically become targeted in a few weeks, so keep on checking the link to see if you’ve been granted access.

Amazon has been eagerly offers some lucrative promotions over the last few years, so keep your credit card accounts linked to your Amazon account, and if you’re targeted for any of these offers, make sure you use them before they expire on May 1.

If you don’t currently have an eligible Amex card, here are several options you might consider:

Amex personal cards:
American Express® Gold Card
The Platinum Card® from American Express

Amex business cards:
The Blue Business® Plus Credit Card from American Express
American Express® Business Gold Card
The Business Platinum Card® from American Express

Also, make sure you read our guide to the best credit cards for Amazon to be sure you’re using the right card when you buy at Amazon.

Check out CNN Underscored’s list of 46 little things you can buy on Amazon that make a big difference.

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