Stimulus check update: A fourth payment would be critical for many, study says They’ll also have to report how much they received for the third stimulus check - including any plus-up payments - in order to figure out how much more they are owed. “Ensuring they use the correct payment amounts will help them avoid a processing delay that may slow their refund,” the IRS says. Individuals can access information regarding their economic impact payment amounts here. (Note: The IRS information only impacts federal stimulus checks, and not ones that were sent out by states like California.) Child tax credit payments More information about the recovery rebate credit can also be found here.