Where Do You Stand Compared To The National Average Grocery Bill? With inflation causing many items’ costs to rise, the national average grocery bill is also taking a hike. The reasons for the higher cost at the grocery store are plenty, some farmers are raising the prices of their crops as a result of rising fertilizer expenses. The epidemic, food shortages, consumer demand, working circumstances, and workplace conditions have all contributed to the skyrocketing supermarket prices. SoFi has compared monthly grocery bills for single, two-person, and four-person families. Honolulu, Hawaii, had the most expensive groceries, while Manchester, New Hampshire, had the least. Under-12s might add $142-$357 to the monthly bill, and teens cost $233-$344 more per child. The study also finds men and younger people have a higher food bill; how much higher has your food bill become?