Thousands of Long Islanders insured through Anthem Blue Cross Blue Shield may be forced to find new doctors after contract negotiations with the Mount Sinai Health System broke down.

The two sides failed to reach an agreement by a Dec. 31 deadline, leaving Mount Sinai physicians out of network for Anthem patients as of the start of the new year. Patients say they are now caught in the middle of a dispute they had no role in creating.

Nicole and James Fischman, of Valley Stream, were hoping for a smooth and healthy start to 2026. Instead, they learned their doctors are no longer covered under their insurance plan.

“To see that there was no agreement reached was really disappointing,” Nicole said.

“My health is finally in check. It’s at a place where it needs to be, and to be told now that I have to find somebody else—it’s not what I want to be doing right now,” she said.

Her husband, James, says the situation is far more complicated than switching everyday services.

“It’s not like you’re going to a store and changing your favorite cereal,” he said. “You’re going to see a group of doctors who have all your information.”

Both Anthem and Mount Sinai are blaming each other for the breakdown in negotiations.

In a statement, Mount Sinai said, “We cannot—and will not—subsidize a for-profit insurer’s margins.”

Anthem says Mount Sinai is seeking steep cost increases, writing that the health system “wants to charge patients 50% more over the next three years.”

Patient advocates warn that the dispute could result in higher costs and disrupted care.

“Your definite out-of-pocket cost is going to be greater,” said James Donnelly, of the nonprofit Pulse Center for Patient Safety.

Donnelly says some patients may qualify for a “continuity of care” exception, which allows them to temporarily keep seeing their current doctors if they are being treated for complex conditions such as cancer. However, those agreements are limited.

“Generally, those agreements are only good for 90 days,” Donnelly said. “So you’ll have 90 days to find an in-network provider.”

For patients like the Fischmans, that offers little reassurance.

“Being told at this point you need to find new doctors—to try and say, ‘OK, now find somebody else’—it’s not right,” James Fischman said.

Under New York state law, hospitals must remain in network for 60 days after a contract ends. That extension provides some short-term protection, but the clock is already ticking.

If Mount Sinai and Anthem do not reach an agreement by March 1, Mount Sinai hospitals—including Mount Sinai South Nassau in Oceanside—would also become out of network for Anthem patients.