Associating a customs VAT import tax invoice with the supplier invoice

I saw an earlier discussion about this general problem.

This is an essential topic in Switzerland too. It is only a small country and most businesses have to import some products and services.

I implemented this completely for Acquisition tax on services on the tax.xml for account_ch - it is tested and working for Services. The situation for Goods is more complicated.

For goods (Waren-Import MwSt), there will be two or three invoices:

  1. invoice from the supplier, no VAT, e.g. EUR 1,0000
  2. invoice from the transport company, they charge an administration fee, for example, CHF 20 + 7.7% VAT
  3. invoice from the Swiss customs. This invoice is the VAT amount. E.g., for the EUR 1,000 invoice at point (1), there would be a customs invoice for 7.7%, that is EUR 77.00, converted to CHF, maybe CHF 90.00

Usually (2) and (3) are combined into the same invoice document from the transport company. The Swiss company makes one payment to cover both (2) and (3).

I was able to successfully enter the value for (3) by using the tax lines at the bottom of the Supplier Invoice screen. I checked the GL and the tax codes tree and I see the correct values. This is really good.

However, there is one problem: if somebody looks at the transport company invoice in Tryton, it is not obvious which supplier invoice it is connected to. Is there a way to make a connection between the supplier invoice (1) and the transport/customs invoice (2)/(3)?