The price of dog poop bags varies greatly according to the the products' material, size, and manufacturing company. Dog poop bags are usually sold in packs of multiples, and pricing varies according to the number of pieces. For a pack of less than 100 dog poop bags, the average price range is between $5 and $10. A pack of 250 or more dog poop bags can cost between $12 and $20. Even the most expensive dog poop bags are still quite affordable, so be sure not to compromise on quality in your search for a good deal.