Corporate Income Tax
Plain English
It's the corporate income tax in Italy. Companies (like SRLs and SpAs) pay IRES on their net profit at a fixed rate, on top of regional IRAP. Sole proprietors and freelancers pay IRPEF, not IRES.
Why it matters
If you set up a limited company in Italy, your accountant will plan around IRES and IRAP every year. The choice between SRL and partita IVA is partly a tax-design question.
Common confusion
Profit, not revenue. IRES is calculated on the company\'s taxable profit after costs. That changes the maths for new businesses with thin margins.
Official source
Agenzia delle Entrate