(Art. 65a VAT Act)
If the electronic procedure is mandatory, all submissions to the FTA must be made electronically via the portal provided for this purpose.
The electronic procedure is mandatory for:
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annual reporting (Art. 35a and 86a VAT Act);
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registration as a taxable person (Art. 66 para. 1 VAT Act);
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filing returns (Art. 71 VAT Act);
correction of errors in returns (Art. 72 VAT Act).