Costco has instant savings on Tide this month! Save an extra $4.50 on the 81-load bottle of Tide Advanced Power Liquid Laundry Detergent. It’s regularly $21.99, but the discount drops the price to $17.49. The next best price is at Walmart where a 150-ounce bottle is $18.93. Paying $0.10 per ounce at Costco versus $0.13 per ounce at Walmart is hands down the better deal.