Free tool
15% Expense Proof Checker
Regime simplificado, Art. 31 n.13 CIRS
As a freelancer on Portugal's simplified regime, you need to document at least 15% of your gross income in professional expenses. Social Security contributions count toward this automatically. For most people paying normal SS, that already covers it. This tool tells you whether you're in the clear, or how much more to document before 31 December.
Total you invoiced for the year, before any deductions.
Activity type
Social Security this year(Seguranca Social)
Your SS contributions (21.4% of 70% of gross, capped at 12 x IAS) count toward the 15% requirement.
Enter your gross income above to check whether you need to document extra expenses.
Everything is calculated in your browser. Nothing you enter is sent to any server or stored anywhere.
Who actually needs to document extra expenses?
Most freelancers paying normal Social Security are covered automatically. Social Security is 21.4% of 70% of your income, which works out to about 14.98% of gross. The threshold is 15.00%. For most income levels, SS gets you there (or so close that rounding closes the gap).
Three groups are genuinely at risk:
First-year SS-exempt freelancers above ~€27,360
If you're in your first 12 months and exempt from SS, the only automatic coverage is the €4,104 fixed deduction. That covers 15% of income up to about €27,360. Above that, you have a real gap that you need to fill with documented invoices by 31 December.
High earners above ~€110,500
SS contributions are capped at 12 times the IAS (Social Support Index) per month. Above roughly €110,500 gross, your SS stops growing but your 15% threshold keeps growing with income. You need to document the gap with professional invoices.
Anyone who had an irregular or late-start year
If you started mid-year, took a gap, or had a year where income and SS timing were misaligned, run the numbers. The default SS estimate assumes a full year at the same rate.
What counts as a documented expense?
The rule counts expenses that are registered in e-Fatura under your NIF, plus Social Security contributions and the €4,104 fixed deduction. The e-Fatura piece is the one you need to actively manage.
- Software and SaaS subscriptions
- Professional equipment and tools
- Office supplies and materials
- Telecommunications (phone, internet)
- Professional services (accountant, legal)
- Foreign supplier invoices (EU and non-EU — register manually on the e-Fatura portal or declare in Anexo B, Quadro 17)
Personal expenses do not count. Only invoices registered as professional expenses under your NIF go toward the 15%.
Common questions
What happens if I don't document the 15%?▼
The shortfall gets added back to your taxable income before the IRS calculation. If you needed to document €3,000 more and didn't, those €3,000 are treated as additional taxable income. At a 28% IRS rate, that's roughly €840 more in tax. The AT doesn't issue a separate penalty for the documentation gap itself, but the higher taxable income produces a higher tax bill.
Does this apply to goods sales too?▼
No. The 15% documented expense requirement in Art. 31 n.13 only applies to income with the 0.75 or 0.35 coefficient (service income). Goods sales use the 0.15 coefficient, which means 85% of revenue is already assumed to be expenses. No additional documentation required.
Can I use foreign invoices (AWS, Vercel, Adobe, etc.)?▼
Yes. Foreign invoices count. They don't appear in e-Fatura automatically (foreign suppliers have no obligation to report to the AT). You have two options: register them manually on the e-Fatura portal as a buyer, or declare them directly in Anexo B, Quadro 17 of your IRS return. Keep the original invoice and payment proof for 10 years either way.
Does this tool work for both EN and PT interfaces?▼
Yes. The calculator works for anyone on the Portuguese simplified regime regardless of their language preference. The tool is currently in English with Portuguese terms shown alongside for portal-matching.
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Track expenses automatically across the year
Instead of checking your coverage in December and scrambling to find invoices, Descodify tracks your documented expenses as you go and shows your coverage against the 15% threshold in real time.
See how Descodify works →