Here are native and migrant fiscal contributions in the EU across different ages. Natives and intra-EU migrants make similar contributions, and burdens become major in old age for every group.

From the above, you could reasonably expect the net fiscal contributions of natives to be the greatest, but they're actually the worst due to the fact that they're more often young and old. (Yes, I know there are migrants' kids among "natives".)

There's variation in how this turns out right now across the EU, with some countries having significantly larger gaps between natives and intra-European migrants in terms of their contributions. They get different people and have different people.

There's also significant variation with respect to the contributions of extra-European migrants, but in this case, the direction of the gaps is generally reversed.