Receipt for closed financial year

Yes, search in the hat at the top right.

2) If you still need to add an expense to previous year before you file your personal income tax. Otherwise, it's pretty pointless. If you have already filed your personal income tax for 2022 income, then it's pointless. Stop it in 2023.3) The invoice date is what it is, but you can effectively change the fiscal date to this year, yes.

2) Yes, indeed.

2) Can I put it in 2023 instead by changing the fiscal date?

3) Can I also change the fiscal date if it is not trade goods? For example, a Telenet bill, my start-up costs or small materials?

2) Yes, indeed.3) In principle, your costs must be included in the year to which they relate. For trade goods, this is the year to which they relate > the year in which you sell them.

For trade goods, you can solve this via the closing inventory (see below module) personal income tax or by updating the fiscal date if this is still possible. For ordinary costs, they normally relate to the year in which you make your purchases. Unless that year has already been submitted via your personal income tax return, in which case you would put them in the next year. Again, via the fiscal date.