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

There’s a limited amount of time for families with eligible children to sign up if they didn’t get the checks automatically, likely because they don’t traditionally file a tax return. 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.

“If parents haven’t already gotten the payment and they’re eligible for it, it’s not too late to sign up,” said Ashley Burnside, a policy analyst at the Center for Law and Social Policy. “They can use the IRS portal, that’s still an option.”

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.

That’s because the monthly money is an advance on a 2021 tax credit, half to be delivered this year and the rest to come when families file their taxes next year.

The American Rescue Plan passed in March expanded the existing child tax credit, adding advance monthly payments and increasing the benefit to $3,000 from $2,000 with a $600 bonus for kids under the age of 6 for the 2021 tax year.

For a family with two children aged 5 and 7 eligible for the full credit, the amount they’d receive is $6,600 ($3,000 for the 7-year-old plus $3,600 for the 5-year-old.)

If they filed a tax return in 2019 or 2020 and had direct deposit, the family started receiving the first $3,300 of the credit in six monthly payments of $550 that will last from July to December.

But if the same family doesn’t traditionally file taxes because they don’t earn enough, they would need to sign up to get the monthly payments via the IRS non-filer tool. 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.

“Families who did not get a July or August payment and are getting their first monthly payment in September will still receive their total advance payment for the year of up to $1,800 for each child under age 6 and up to $1,500 for each child ages 6 through 17,” the IRS said in a Sept. 15 statement, coinciding with the third monthly payment going out to families.

“This means that the total payment will be spread over four months, rather than six, making each monthly payment larger. 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.

As each month passes, families who just signed up will get slightly larger payments as the IRS works to make sure they get the first half of the credit ahead of tax time. Those that wait to sign up through the Code for America tool in November will get the entire first half of the credit in one check in December, according to a Treasury official.

Families that traditionally don’t file and sign up for the credit now can also claim any stimulus payments from the last year and a half they were eligible for but didn’t receive.

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. To get the credit, though, they will have to file a 2021 tax return.

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.

“We would hate for money to be left on the table when people are hungry, when people have housing insecurities, food insecurities,” said Otis Rolley, senior vice president of the U.S. equity and economic opportunity initiative at the Rockefeller Foundation.

Signing up now could also make it easier for families to get the child tax credit going forward. Currently, Democrats are working to pass legislation that would continue the enhanced credit, including monthly payments, in the coming years.

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