For families with strong habits to curb spending, sticking to their strict household budget is the plan

Extremely frugal families are coping with record-high inflation by doing what they’ve always done: not spending money.

Art Shillito, along with his wife, Janelle, forgoes shopping lists and mostly buys marked-down items.

That's how much the Burnt Hills, N.Y., couple say they’ve spent on average per month this year to feed their family of 11, which is below last year’s monthly average of $500. They also own their home and have no debt.

With high inflation costing many Americans more, a small but enthusiastic group of already-super-frugal people are taking their saving strategies further.

Some of their tactics: checking wholesalers for sharply reduced “distressed” foods with damaged packaging; designating no-spend months when they abstain from buying nonessentials; and auditing one or two categories of spending to see where they can shave costs.

The Shillitos grow most of their vegetables and some fruits in five gardens. Last year, they harvested 770 pounds of food for their family.

The couple buys in bulk and shops directly with restaurant supply stores, once snagging a 50-pound bag of flour for $14.96 at a wholesale food distributor.

Grocery prices rose 11.9% in May from the same month a year ago, with meat, poultry, fish and egg prices climbing at double-digit rates, according to Labor Department figures, testing everyday shoppers and the extremely frugal alike.

Mr. Shillito records every food purchase in a spiral notebook and noted that they ended up spending $265.18 in January, because some deals were too good to pass up, like one for 1,000 cupcake liners for $7.

For the Shillitos, a gallon of milk now costs $3.89, up 8% since January when they paid $3.59. They don’t want to reduce the amount of milk they drink, but save money through a Milk Club at a local dairy that awards them a free half-gallon of milk after they buy five gallons.

Their 38 chickens provide the family with eggs, which is a big savings as the price of eggs has risen 32.2% in the past year.

They try to keep nonfood costs down, too, hand-washing dishes and turning off lights when they leave a room. Their 12-passenger van eats up a lot of gasoline, so they use their smaller car when possible and combine all errands into one trip.

says Laura Muresan, Mr. Shillito’s sister.