2026 deadlines for solo entrepreneurs
January
| Date | Obligation | Details |
|---|
| Jan 10–20 | SS contribution (Oct income) | Monthly payment to Segurança Social |
| Jan 15 | Q4 SS declaration | Declare Oct–Dec income to SS |
February
| Date | Obligation | Details |
|---|
| Feb 10–20 | SS contribution (Nov income) | Monthly payment |
| Feb 15 | Agregado familiar | Confirm/update household on AT portal |
| Feb 15 | Q4 VAT return | Declaração Periódica de IVA (Oct–Dec) |
| Feb 25 | e-Fatura review | Categorize expenses on e-fatura portal |
March
| Date | Obligation | Details |
|---|
| Mar 10–20 | SS contribution (Dec income) | Monthly payment |
| Mar 31 | Deduction confirmation | Confirm pre-filled Anexo H deductions on AT |
April
| Date | Obligation | Details |
|---|
| Apr 1 | IRS filing opens | Modelo 3 submission for 2025 income |
| Apr 10–20 | SS contribution (Jan income) | Monthly payment |
| Apr 15 | Q1 SS declaration | Declare Jan–Mar income to SS |
May
| Date | Obligation | Details |
|---|
| May 10–20 | SS contribution (Feb income) | Monthly payment |
| May 15 | Q1 VAT return | Declaração Periódica de IVA (Jan–Mar) |
June
| Date | Obligation | Details |
|---|
| Jun 10–20 | SS contribution (Mar income) | Monthly payment |
| Jun 30 | IRS filing closes | Last day to submit Modelo 3 |
July
| Date | Obligation | Details |
|---|
| Jul 10–20 | SS contribution (Apr income) | Monthly payment |
| Jul 15 | Q2 SS declaration | Declare Apr–Jun income to SS |
| Jul 31 | AT issues assessment | Nota de liquidação (refund or payment due) |
August
| Date | Obligation | Details |
|---|
| Aug 10–20 | SS contribution (May income) | Monthly payment |
| Aug 15 | Q2 VAT return | Declaração Periódica de IVA (Apr–Jun) |
| Aug 31 | IRS payment/refund | Payment deadline if you owe; refund issued |
September–December
| Date | Obligation | Details |
|---|
| 10th–20th monthly | SS contribution | Monthly payment |
| Oct 15 | Q3 SS declaration | Declare Jul–Sep income to SS |
| Nov 15 | Q3 VAT return | Declaração Periódica de IVA (Jul–Sep) |
Recapitulative statement (Declaração Recapitulativa)
If you invoiced services to businesses in other EU countries during any quarter, you must also file a recapitulative statement for that quarter. Same deadline as the VAT return. Easy to miss, AT doesn't remind you.
Notes
- VAT returns only apply if you're on the standard VAT regime (not if exempt under Article 53)
- SS contributions are paid between the 10th and 20th of each month, no reminder from SS
- Bold items are the deadlines most people miss
- All filings are done through the Portal das Finanças (IRS, VAT) or Segurança Social Direta (SS)