Acconto e saldo
Also known as: advance and balance payments, tax advance
Italian income tax isn't only paid in arrears: each year you settle the balance (saldo) for the past year and prepay an advance (acconto) toward the current one — normally 100% of the prior year's tax, split into two instalments in June and November (Legge 97/1977). The forfettario substitute tax follows the same schedule.1
What this means for you
This causes the classic year-two shock: in your second year you can pay last year's balance and this year's advance together. Budget for it and set tax money aside as you earn. A newly started activity owes no acconto in its first year.
Sources
Every figure on this page is grounded in primary sources — the same standard as the TaxCompass chat. This is sourced orientation, not tax advice.