Costco Closed on Labor Day 2021 by Rhonda September 6, 2021 738 9/6/21. Costco will be closed on Monday, September 6, 2021, in observance of Labor Day. 0 FacebookTwitterPinterestThreadsBlueskyEmail previous post NEW Kirkland Signature Nativity Set at Costco! next post Costco.com Labor Day Sale! 2021 You may also like Costco Coupon Book SEPTEMBER 2025 Costco Hot Buys Sale JULY 2025 Peaches and Cream Bar Cake from the Costco... Fried Chicken and Waffles at Costco! Costco Coupon Book JUNE / JULY 2025 NEW Costco Executive Member Benefits Starting June 30,...