Costco Closed on Labor Day 2021 by Rhonda September 6, 2021 663 9/6/21. Costco will be closed on Monday, September 6, 2021, in observance of Labor Day. 0 FacebookTwitterPinterestEmail previous post NEW Kirkland Signature Nativity Set at Costco! next post Costco.com Labor Day Sale! 2021 You may also like Costco Weekend Update: April 25-27, 2025 Costco Weekend Update: April 18-20, 2025 Kirkland Signature Baby Wipes – Costco Sale! Strawberry Streusel Cheesecake at Costco! Yankee Candle Car Jar Ultimate Air Fresheners –... Costco Coupon Book APRIL 2025