Millions of American families with kids have received three monthly payments since July totaling $45 billion through the new enhanced child tax credit.

If they haven’t received the checks in their regular tax return, they will need to sign up for them. Families who are eligible can only register in a short time. The IRS non-filer portal will be open through Oct. 15, according to the agency, meaning there’s just one month left for families to use it.

Ashley Burnside, policy analyst with the Center for Law and Social Policy said, “If parents haven’t yet received the payment and are eligible for it,” They can still use the IRS portal.

After October, families will be able to use GetCTC.org, a site launched by Code for America in collaboration with the U.S. Department of the Treasury and the White House, to sign up for the credit through mid-November, according to a Treasury official.

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Larger checks

Families that enroll for the credit now will see larger remaining payments than those who have been getting them monthly since July, when the checks began.

The monthly cash is an advance for a 2021 tax credit. Half of the money will be sent this year, and half the next.

American Rescue Plan, which was approved in March, increased the child credit benefit by increasing it to $3,000 per month from $2,000 and adding a $600 bonus to children 6 or younger for the 2021 tax years.

A family of two children, aged five and seven, would be eligible to receive $6,600. This includes $3,600 for each child under six years old, as well as $3,000 for the younger siblings.

The credit will be paid out in monthly installments of $550 if the family filed their tax returns in 2019, 2020, or both.

If the family isn’t able to file their taxes due to insufficient income, then they will need to register to receive the monthly payments through the IRS non-filer. If the family missed the July payment but signed up in August — as about 1 million families did — they’d still get $3,300 before December.

The IRS stated in a September 15 statement that families who didn’t receive a July payment or August payment but received their first monthly payment in September would still get their full advance payment of $1,800 per child below the age of 6 and $1,500 each child 6-17.” This coincides with the third monthly installment being sent to families.

This means the monthly payments will now be larger because they are spread out over 4 months rather than 6 and that total payment will not exceed $1,800. For these families, each payment is up to $450 per month for each child under age 6 and up to $375 per month for each child ages 6 through 17,” the agency said.

The IRS will increase the monthly payments for families that have just signed up, to help ensure the family receives the full credit. A Treasury official said that those who do not sign up using the Code for America tool by November 30th will be able to receive all of the credit in December.

If a family has not previously registered for the credit, they can still claim the stimulus payments that were available in the past year.

Why families should sign up now

To be sure, if a family fails to sign up for the new child tax credit this year they will miss out on advance payments but can still get the money in a lump sum next year. They will need to file a tax return in 2021 to get the credit.

Even those who usually do not file taxes because they don’t make enough money can get the credit — the enhanced version was made fully refundable to ensure it reaches the most vulnerable families.

Still, experts say that everyone with an eligible child should sign up as soon as they are able, unless they are part of a family that knows they want to opt out and receive the benefit in a lump sum next year.