Households in Massachusetts that use federal SNAP benefits to help pay for food will see the amount they receive drop by an average of $150 after today. That's because a federal COVID-era enhancement of the program is coming to an end.

"It will impact the entire caseload, which is 640,000 households and over a million residents," said Brittany Mangini, associate commissioner for food security and nutrition programs at the state Department of Transitional Assistance.

"I think, unfortunately, it's going to really undermine a lot of the efforts that we have to mitigate food insecurity across the Commonwealth," Mangini said. "But one thing that we've done, is try to be as proactive as possible with getting information out to folks so that we can address the impact that it's going to have on their overall household budget."

The state set up a website detailing resources to help people reduce the impact of the loss in food assistance, Mangini said.

Advocates for food security in Massachusetts say the sunsetting of the federal SNAP expansion is coming at a difficult moment, with food prices and other expenses especially high.

"We are worried because we're doing everything we can," said Catherine Lynn of the Greater Boston Food Bank. "At a time when we're already seeing elevated need and demand on our system, and at a time when food, gas, energy, housing, medical... [and] childcare costs are through the roof, the cost of living is so expensive... every single income stream is going to be so important."

Lynn said she expects the sudden drop in benefits to increase reliance on assistance from the Greater Boston Food Bank, which distributes food to 600 food pantries, meal programs, shelters and markets around the state.

"We know that this support has directly helped people put food on the table and to alleviate that worry about feeding themselves and feeding their kids," said Erin McAleer of Project Bread. "The folks that are calling Project Bread are worried. We talked just earlier this week to a senior citizen from Fitchburg who says she'll now be receiving only 23 dollars a month."

Governor Maura Healey's supplemental budgetapproved Wednesday by the state House of Representatives included $130 million to enhance SNAP benefits for the next three months. Lynn said that would be enough to cover 40 percent of the reduction during that period.

"What I proposed doing through that Senate budget was providing people a little bit more of a glide path so it wouldn't be so abrupt," Healey said Thursday on GBH's Greater Boston. "So that people wouldn't go from, you know, overnight losing what's estimated to be an average of $150 a month."

The state Senate is expected to consider the supplemental budget next week.

"Massachusetts has a real opportunity here to be a leader," Lynn said. "I have high confidence that the legislature is going to pass this supplemental budget, and I think it will make a difference and a huge impact in terms of ... [reducing] that shock that people are going to feel. And so it won't be feeling like someone's pulling a rug underneath them."

But the supplemental budget, Lynn pointed out, does not include any increased funding to cover increased reliance on food banks like hers.

"So we are talking to our legislators," she said. "In a state of emergency, ensuring that the emergency food system is sustained with the right level of funding is going to be critical."

This story includes reporting by Mary Blake.