According to the BMF letter of 24 April 2020 (link), it is now possible to apply for a (partial) refund of the advance payments already made for 2019 by means of a lump-sum loss carryback. The lump-sum loss carryback amounts to 15% of the income on which the advance payments for 2019 were previously based. The amount of loss carryback is limited to EUR 1,000,000. In terms of time, such an application is possible as long as the assessment for 2019 has not yet been made, but no later than 31 March 2021.
In addition, the Federal Ministry of Finance takes into account the problem that a loss carryback from 2020 after 2019 will normally not yet be formally possible when assessing the tax year 2019. In the amount of the subsequent payment due to the loss carryback already taken into account, the BMF therefore grants an interest-free deferral until one month after the announcement of the tax assessment 2020 at the latest. For this purpose, the taxpayer should point out at the time of filing the tax return 2019 that he/she still assumes a not inconsiderable negative amount of income for the year 2020 and requests a deferral in accordance with the BMF letter. Finally, the deferred subsequent payment for 2019 will not apply if the assessment for 2020 results in a loss carryback within the meaning of § 10d (1) EStG.