According to § 18 I UStG, the entrepreneur has to submit a pre-registration according to the officially prescribed form by the 10th day after the end of each pre-registration period. From 2005 this must be done electronically. In the pre-registration he has to calculate the sales tax himself (as an advance payment). According to § 18 II UStG, the pre-registration period is basically the calendar quarter.
In special cases it can be shortened to one month. If the sales tax does not exceed € 512, the tax office can exempt the entrepreneur from the obligation to submit the advance notification and pay the advance payment. The advance tax return is subject to review. The VAT paid is offset against the VAT actually incurred in the tax return. There is a tax credit or a tax payable burden.
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