The due date for VAT depends on the accounting method: Agreed charges or collected charges
Under the agreed consideration method, the tax becomes due at the time of invoicing, whereas under the collected consideration method, the tax only becomes due when the money is actually received or paid.
VAT - Collected consideration method
In the case of the collected consideration method, the VAT due is due at the time of invoicing. Similarly, input tax on goods and services purchased can be claimed on the date of the supplier's or service provider's invoice.
VAT - Agreed consideration method
In the case of the agreed consideration method, the actual incoming or outgoing payment is the decisive point in time for the tax assessment. Accordingly, VAT on customer invoices is due at the time of receipt of payment, while the input tax deduction on vendor invoices can be claimed at the time of payment.
The accounting method can be selected independently of the method used to calculate the VAT: I.e. the settlement according to agreed as well as received remuneration can be applied both to the effective method and to the balance and flat rate method.
In principle, according to the VAT Act, invoicing is based on agreed charges. However, upon request, the Swiss Federal Tax Administration (FTA) also allows taxable persons to invoice according to the remuneration received.
From a financial perspective, the two accounting methods are the same, as a VAT payer ultimately pays exactly the same amount of tax in both procedures.