If you received a full $2000 credit this year for a child dependent under age 16, and you claim the same dependent on 2021, then this year you would expect to receive advance payments of $1800 ($300 per month over 6 months), and the remaining $1200 would be applied as a credit on your tax return. Assuming your income and all other tax facts are the same, then since the credit applied on the actual tax return would be $800 less than the credit applied on the tax return last year, you would expect to have your refund be $800 less or your tax due $800 more. But you will have also received the advance payments.
