An autónomo's deductible expenses are those tied to the business activity, backed by supporting documents (normally an invoice), and recorded in your books: only when all three conditions are met do they reduce your taxable net income. Typical examples include the monthly social security quota, software and equipment, professional advice, or the business share of home utilities when you work from home.
In an audit the burden of proof is on you: without an invoice in your name and a clear link to the activity, the tax agency can reject the expense. kontora records your expenses and prepares draft tax forms with deadline reminders; filing is always reviewed and signed off by you or your advisor.
Rather have this calculated for you?
kontora generates your tax forms box by box, tells you how much to set aside and reminds you before every deadline.