Costco.com 4th of July Sale! by Rhonda July 5, 2021 293 7/4/21. Even though Costco stores are closed today in observance of Independence Day, costco.com is open and is having a huge sale! Check out hundreds of deals at costco.com, while supplies last. 0 FacebookTwitterPinterestEmail previous post Costco Closed on the 4th of July next post Savannah Fabric Hamper with Lid – Costco Sale! You may also like Happy Hop Shark Cave Adventure Inflatable Water Slide... Lemon Meringue Cheesecake from Costco’s Bakery! Squishmallows Macaron Lip Balms at Costco! Costco Coupon Book MAY / JUNE 2023 Costco Business Center Coupon Book MAY / JUNE... Hand Dipped Strawberries at Costco!