U.S. companies that collect waste for recycling are weighing higher prices and other changes to their operations since China upended the industry when it stopped accepting much of the scrap material Americans have been shipping there for decade.

The top two solid waste services companies in the U.S., Waste Management Inc. WM -0.38% and Republic Services Inc., RSG 0.27% both recently pulled back profit projections in their recycling divisions based on China’s new policies, which have created a glut in scrap markets and sent global prices for scrap material plummeting.

“At this point in time, we have zero volume going to China,” said Richard Coupland, vice president of municipal sales at Republic Services. “We are still able to move material, but our economic model is completely upside down.”

More in Logistics XPO Logistics Adjusts Guidance Off Customer Bankruptcy

According to the Institute of Scrap Recycling Industries Inc., 31% of U.S. scrap commodity exports worth a total of $5.6 billion were sent to China last year.

Republic Services processes about 6 million tons of paper, glass, plastics and other materials for recycling each year under contracts with roughly 2,400 municipalities in 40 U.S. states and Puerto Rico. Before this year, about 40% of that was shipped to scrap buyers in China who would break it down and make new boxes, packaging, toys and other goods.

It was cheap for recycling collectors to send scrap to China because ocean carriers offered deeply discounted prices to get shipping containers back to Asia after they had arrived at U.S. ports packed with goods made in Chinese factories. “We were happy to send material back in them for pennies on the dollar,” Mr. Coupland said.

Now it’s gotten more complicated. Mr. Coupland said Republic Services has found new buyers in Malaysia, India and other markets, but fewer ships make direct trips there from the U.S., driving up transportation costs. Global prices for used materials have plummeted, so Republic loses money on most of the recycled scrap it now sells overseas.

That cost is increasingly likely to get passed along to U.S. households and businesses. Some cities and towns could decide that keeping their recycling services is simply too expensive.

“ Recycling programs will face challenges unless the cities begin to envision a more durable business model, ” — Richard Coupland of Republic Services

“Recycling programs as a whole will face challenges unless the cities begin to envision a better, more durable business model,” Mr. Coupland said. That would mean higher prices on contracts with cities that he said could lead average household prices for curbside recycling services to double to about $7 monthly.

Customers can also help keep costs low by doing a better job of sorting their recycling and trash, many in the waste services business say. China’s new rules raise barriers to contaminants in waste imports, and U.S. recycling collectors would have to upgrade their equipment and hire more workers to meet the tougher standards.

Mr. Coupland said in major markets like Dallas, Philadelphia and Phoenix, from 30% to 50% of the material in recycling bins may be contaminated or can’t be recycled. “So not only do you have to pay the cost to get it to processing facility, then you have to separate the trash and pay even more money to move it to disposal facility,” he said.

“The key is we’ve got to get the word out,” Mr. Coupland said. “Everybody’s got a role, everybody has to get involved. If we can all get better at what we throw away, that will help us tremendously on the back end.”

Write to Erica E. Phillips at erica.phillips@wsj.com