It would be very difficult to determine the exact amount of the refund from the Unemployment Exclusion as it depends on your tax rate and the amount of withholding.
However, you could guestimate by taking your effective tax rate and multiplying it by your unemployment earnings (up to $10,200).
Keep in mind the IRS has asked that you not file an amended return for this adjustment - there is no need to file an amended return (Form 1040-X) to figure the amount of unemployment compensation to exclude. The IRS will refigure your taxes using the excluded unemployment compensation amount and adjust your account accordingly. The IRS will send any refund amount directly to you
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