If you’re a Costco member, check your mailbox (or the membership desk at your local store) for the next edition of the Costco Coupon Book, which is valid Aug. 25 - Sept. 21, 2025 .
While we include every page of the September Costco coupon book below, you won’t need a physical copy of the book to claim these discounts at Costco. And there aren’t any Costco coupons that you’ll need to cut out to get the sale prices. The savings are automatic for anyone with a Costco membership, whether you’re shopping Costco online or in the store.
But I should warn you that Costco’s online prices are nearly always higher than in-store prices (especially for pricey things like furniture), and Costco doesn’t offer price matching for online vs. in-store. That’s why I always recommend shopping in-store to get the best Costco deals. I’ve got a few other Costco price hacks if you’re curious.
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Best September Costco Coupon Book Deals
Our team of expert shoppers picked the best deals from the September Costco ad, plus gathered in-store prices so you can see just how much you'll save with each deal.
Groceries
Personal Care Items
Household Items and Paper Goods
Detergent and Toilet Paper
Baby Deals
September Costco Coupon Book (Valid Aug. 25 - Sept. 21, 2025)
Below, you can flip through the full ad scan of this month’s Costco coupon book. Use the right and left arrows to scroll through the pages, or select a page to enlarge it.
Costco Monthly Ad Scan
The Costco Coupon Book is a printed flyer that lists current sale prices available online and in-store.
Costco calls this printed booklet the "Member-Only Savings (In-Warehouse and Online)," but most shoppers simply refer to it as the monthly Costco Coupon Book.
A new Costco Coupon Book comes out in the mail just about every month. The deals inside the printed booklet are usually valid for 26 days, but the exact dates will be listed on the front cover. Deals periods typically start on a Wednesday and end on a Sunday.
The current Costco Coupon Book deals are valid Aug. 25 - Sept. 21, 2025.
This month's Costco Coupon Book is valid Monday, Aug. 25 - Sunday, Sept. 21, 2025. This aligns with our original prediction.
As for the next Costco Coupon Book after this one, we predict it'll be valid Sept. 24 - Oct. 19, 2025.
KCL TIP: Costco usually mails out a new Costco Coupon Book about a week before the sale actually begins.
Tips for Using the Costco Coupon Book
1. Remember that sale cycles rotate, so you'll see different brands and products on sale each month.
While many product categories go on sale every single month at Costco (like vitamins, laundry detergent, and oral care), the specific brands and products will rotate.
So if you don’t see the brand of toothpaste you want on sale this month, just wait a month or two, and you'll likely see it pop up in a future coupon book.
2. Look for the '+Costco.com' icon to know if the sale price is available online.
Some of the low prices advertised in the Costco coupon book will be available in store only. That’s because Costco’s online prices aren’t always as low as their in-store prices, since they have to factor in shipping and handling.
But many of the items in the coupon book will have a red icon that says “+Costco.com” next to the price. This means that the product is available at the same price online. If it’s missing that icon, you can assume the online price will be higher than advertised.
KCL TIP: Because of potential price differences, I always recommend shopping in person at your local warehouse to get the absolute lowest prices at Costco.
3. Request a price adjustment if you see a price drop on something you bought within the last 30 days.
Did you recently buy something at Costco, only to see it go on sale the very next week? As long as you’re not in the business of reselling items, you’re totally allowed to ask for a Costco price adjustment for most purchases made within the last 30 days.
To request a price adjustment for something you bought in the warehouse, just visit the Returns desk at the Costco location where you made the purchase. For online purchases, complete the price adjustment request form online.
Note: Costco will never match their in-store prices to online prices and vice versa. Costco's online prices are usually a little higher to cover shipping and handling costs.
4. Didn't get a mailed copy? Check your mailing address in the Costco app.
As long as you're a current Costco member, you should receive a Costco Coupon Book in the mail each month. Costco will send it to the mailing address on file for the primary member on the account.
If you didn’t receive a book, make sure your mailing address is listed correctly in your Costco.com account online or in the Costco app.
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