Take inventory of your shopping list. Separate the items that are taxable from the ones that are not subject to sales tax. Some grocery stores charge sales tax for bottled water, soft drinks, juices and snack food. The sales tax on these items can be budget killers, not allowing it to stretch very far. Estimate how much these items may cost you, and then figure out the sales tax. If your sales tax hits $5.00 or greater you should consider eliminating some items such as a few soft drinks and some of the snack food items. Eliminating unnecessary sales tax can help make your food budget stretch.