Here’s a nice Amazon deal for you. Right now the Hefty Strong Tall Kitchen Trash Bags 13 Gallon 90 ct is on sale for $14.99 (reg. $17.49), plus you can save 5% more when you subscribe and there is a 20% coupon on the item page. That makes the final price just $11.99. Here is the link to pick up a box:
Hefty Strong Tall Kitchen Trash Bags 13 Gallon 90 ct – only $11.99 with sale, subscription and coupon (reg. $17.49)