[ar0]

But be aware that many European countries know laws against quasi-self-employment ("Scheinselbständigkeit" in German) to avoid people becoming self-employed to avoid social security taxes. So, even if you set-up your own company but this company only serves one client (your de-facto "employer"), you and/or your employer might be liable for social security payments neither of you did expect. So even such a set-up might be too risky for some companies to consider.

[gizi]

In Germany itself, that would indeed be a major issue. Imagine, however, a company from Canada employing a German in France? Which country would manage to get in a position that they could collect social security payments? Germany would not see any part of that situation under its eyes. Canada just sees invoices coming in from abroad. France has no clue as to what that German does or with whom. This situation could last for decades and no government would be able to even ask relevant questions. You see, that German is not a resident of Germany. I cannot imagine the German administration sending questionnaires overseas. The French may want to collect local taxes, but they would have no serious basis, or even information, for collecting income tax or social security contributions. Where exactly would they be verifying anything? In other words, if you confuse the situation sufficiently, not one of those slow and bureaucratic government administrations could ever deal with it. Not in our lifetime.

[throwaway12309]

Portugal has the same issue, if 70%+ of your company income is from a single entity, the company is taxed as a self employed person and not a company. So technically, the paying company doesn't have to pay nothing, but the receiving company will be responsible for those contributions. But there are ways around it and limitations, for example, in PT doesn't apply if you have employees or if the volume of business if over a certain amount or if ownership is divided by two (or more) people (if you are married, you can name your partner as a shareholder when you create the company and get around it easily)

[jotm]

That German would be paying French income tax, since he's a resident. Unless he's listed as a resident in Germany and living in France without registering.

The other taxes, well, it's up to the person. If he wants a pension, he'll pay them in some country.

But what do I know, everyone I know is breaking some law in regards to taxes, so I might not be the best person to listen to...