The clock is ticking for families who haven't signed up for their enhanced child tax credit (CTC) payments yet.

Many families have received four advance payments of the enhanced benefit, thanks to the American Rescue Plan. But those who are eligible and have not signed up yet have until Nov. 15 to do so in order to receive half of their total CTC this calendar year. Otherwise, they can claim the entire CTC when they file their 2021 taxes next year.

Most families don't need to do anything to receive their payments, which have been distributed monthly since July. But because the credits were made fully refundable this year, many low-income families who typically do not file a tax return are eligible to receive them for the first time. The IRS needs those taxpayers' bank account information or home address in order to send them their advance payments.

Other families who also haven't received their checks automatically for whatever reason can also register with the IRS.

To sign up, parents can use GetCTC.org, made by Code for America in collaboration with the U.S. Department of the Treasury and the White House, or go directly to the IRS's website and use the CTC update portal.

Families that sign up now will receive a larger catch-up check in December than those who have been receiving payments since July, because the IRS will pay out six months worth of payments.

All families will receive the other half of the CTC when they file their tax return next year.

It is not clear if families will continue to receive the enhanced CTC past this year, although Democrats have included it in their social spending legislation. Negotiations on the bill are ongoing.

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