More than 700,000 Americans will receive a supplemental stimulus payment this week as the IRS continues to process 2020 tax returns, the agency said Wednesday.

These "plus-up" payments, as the IRS calls them, will be sent to taxpayers who received a third stimulus check based on 2019 income, but qualify for more money based on their 2020 returns. The agency estimates it will send out more than $1.2 billion in supplemental payments, many of which should have hit bank accounts by April 14.