Some 39 million American families on July 15 will get the first of six advance monthly payments of the enhanced federal child tax credit.

However, some of those families should elect to not receive the monthly payments, say financial experts, and instead wait to claim the entire credit when they file their 2021 taxes next year.

In June, the IRS opened an online portal for families where they can inform the government agency that they don't want to receive the advance payments.

"It's important to allow that ability to opt out of these payments because we don't know how people have budgeted their tax refunds," said Elaine Maag, a principal research associate at the Urban-Brookings Tax Policy Center. "And so if it's important to them that they receive this credit as one lump sum payment, we want to make sure people still have that option."

If a family has not yet unenrolled for the advance monthly payments, they will, in fact, receive one through direct deposit or by paper check this month, as the last day to update the preference for the July disbursement was June 28. However, families can still tell the IRS not to send the payments going forward, meaning they won't get the money for the remaining five months through the end of the year.

A credit against money owed

Families who tend to owe money to the IRS when they file their taxes may want to use the full credit next year, as opposed to getting half of it in advance, because the benefit offsets what they ultimately have to pay.

"It's protection from owing a surprise amount of money to the IRS," Maag said.

The enhanced child tax credit is part of the American Rescue Plan signed into law by President Joe Biden in March. For 2021, the credit increases to $3,000 from $2,000 per child under the age of 17 and gives an additional $600 benefit for children under the age of 6.

That can either come in monthly payments — $250 per month for children between the ages of 6 and 17 and $300 per month for those under the age of 6 — or can be claimed as a lump sum on 2021 taxes.

The full credit is available to all children ages 17 and under in families with 2020 or 2019 adjusted gross income of less than $75,000 for single parents and $150,000 for a married couple filing jointly, and ends for individuals earning $95,000 and married couples filing jointly making $170,000, though they'd still be eligible for the regular child tax credit.

A lump sum for spending

Other families may want to opt out of the advance credit because they'd rather get a large lump sum to spend at once instead of smaller amounts of money each month.

For many Americans, their tax refund is the largest windfall they see all year and is something they rely on in their budget. These families may be planning on a large tax refund to use for a purchase, such as a car or a refrigerator or other household item.

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"We don't want to take away that ability from people," Maag said.

Of course, because the credit is larger than in previous years, it's not a given that those who do claim the advance monthly payments will automatically see a smaller tax refund than they're used to. Still, some families may prefer to get the extra cash at one time instead of having it spaced out.

Tax planning

For some families, likely those on the higher end of the income range eligible to receive the credit, receiving the monthly payments in advance may throw off tax planning they have in place.

This generally applies to families who not only have income from wages but might have capital gains or other money coming in and so have the IRS withhold more than the standard amounts often taken out of biweekly paychecks by an employer.

"If they all of a sudden get $2,000 or $1,000 delivered to them during the year, there may be a mismatch when they come to file their tax return," Maag said.

Thus, they may also prefer to use the entire credit when they file to offset any taxes they may owe. If they don't have any additional tax liability, they'd get the money back in a refund.

To see how much you could expect to receive, personal finance website Grow created a calculator that weighs your filing status, annual income and the number of dependents you have.

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