Yes. Every day interest is added to your account.
If you have a mortgage of €100k @4% , the annual interest is €4,000 so the daily interest is €10.96
It's a tiny bit more complicated than that, because on a particular day each month(?) they capitalise the interest.
So they are charging interest on €100k today, but they add €339 to it tomorrow for the interest charged but not capitalised over the last month.
But if you have a recent statement, you can calculate it yourself very closely.
Brendan