It’s a happy day for Montclair residents who have been throwing out their yogurt cups and other plastics that aren’t marked with a 1 or 2.

Starting on Monday, Nov. 6, residents will be able to put #5 plastics — including many types of yogurt containers — in with their plastics and glass for recycling.

The news was posted on the township website Monday and sent out to residents in an email blast.

“I think the public will be pleased with this, frankly because yogurt containers are a common sight in the Montclair waste stream,” said Gray Russell, Montclair’s sustainability officer.

Montclair has a contract with Atlantic Coast Fibers, a materials recovery facility in Passaic. Atlantic Coast Fibers sorts the recycling shipments and then sells them to companies that buy recyclable materials.

Russell said that Atlantic Coast Fibers recently told Montclair about the change.

“They’ve told our Department of Community Affairs ... you can start recycling #5.”

The change is due in part to improved technology in the plastics industry that processes #5 plastics, Russell said.

Some local grocery stores will accept certain varieties of plastics. Most have collection bins for plastic shopping bags, and the Bloomfield Avenue Whole Foods has bins for several varieties of paper, plastic and compost.

Plastics with the #1 and #2 symbols, which are polyethylene products, are the most valuable recyclables from a buyer’s standpoint, Russell said, because they are the easiest to recycle.

These include most varieties of bottles, including for beverages and household cleaning products. “That’s what they really want. And frankly, numbers 3 through 7 ... are not as easily recyclable,” Russell said.

In addition to the announcement about #5 plastics, the township is also announcing a change in the handling of waxed paper cartons.

Montclair accepts cartons, including aseptic packaging containers, such as juice boxes and broth containers, and milk cartons and large juice cartons, for recycling. However, with the changes, those items will go into the commingled recycling bin instead of with the paper.

Cartons should be flattened, with caps and straws removed.

Russell said that the most important message to take away from the announcements is that residents should recycle correctly: pay close attention to what is allowed into recycling collections and what is not.

Montclair receives a small amount of money per ton of recycling, anywhere between $3 and $10, Russell said.

The biggest saving comes from each ton of garbage that is diverted from the incinerators. It costs Montclair $85 per ton of garbage to burn it in the incinerator.