Prazos

No deadline slips by.

Your personal deadline calendar for Social Security and the Tax Authority in Portugal. Four questions, a full year of dates — and what happens if you miss one.

How it works
JFMAMJJASOND10days

Your answers

Example filled in — change the answers and the calendar updates.
Month you registered your activity with Finanças.
Who are your clients?
Pick all that apply.
Expected income this year
Did you owe tax on your last IRS?
This decides the advance payments.

Your year of deadlines

October 2026
20
Tue
SS contribution for September 2026 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
31
Sat
Quarterly Social Security declaration file
Falls on a non-working day — handle it by Friday 30 October.

Declare your income for Q3 2026 in Segurança Social Direta.

If you miss it: fine of €50–250 and SS sets the minimum €20 contribution. You can still file late until 31 December 2026.

Source: CRC art. 151.º-A, 233.º · Guia ISS 2026verified+ Google Calendar
November 2026
20
Fri
SS contribution for October 2026 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
December 2026
20
Sun
SS contribution for November 2026 pay
Falls on a non-working day — handle it by Friday 18 December.

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
21
Mon
IRS advance payment pay

Only if AT sends you the document (about a month ahead). Under €50 is not paid.

If you miss it: interest.

Source: CIRS art. 102.ºverified+ Google Calendar
January 2027
20
Wed
SS contribution for December 2026 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
31
Sun
Quarterly declaration + annual income file
Falls on a non-working day — handle it by Friday 29 January.

Declare Q4 2026 and confirm your annual income for 2026.

If you miss it: fine of €50–250; late filing possible until 31 March 2027.

Source: CRC art. 151.º-A n.º 5 · Guia ISS F4verified+ Google Calendar
February 2027
20
Sat
Annual SS adjustment pay
Falls on a non-working day — handle it by Friday 19 February.

If January’s confirmation produced an amount due, pay by this date.

If you miss it: late interest.

Source: Guia ISS 2026, F4to confirm+ Google Calendar
20
Sat
SS contribution for January 2027 pay
Falls on a non-working day — handle it by Friday 19 February.

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
28
Sun
Expenses in e-fatura do
Falls on a non-working day — handle it by Friday 26 February.

Assign your 2026 invoices to the activity on Portal das Finanças.

If you miss it: missing expenses up to the 15% are added to taxable income.

Source: CIRS art. 31.º n.º 13–16 (DL 49/2025)verified+ Google Calendar
March 2027
20
Sat
SS contribution for February 2027 pay
Falls on a non-working day — handle it by Friday 19 March.

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
April 2027
1
Thu
IRS for 2026 opens file

You can file Modelo 3 with Anexo B from today.

Source: CIRS art. 60.ºverified+ Google Calendar
20
Tue
SS contribution for March 2027 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
30
Fri
Quarterly Social Security declaration file

Declare your income for Q1 2027 in Segurança Social Direta.

If you miss it: fine of €50–250 and SS sets the minimum €20 contribution. You can still file late until 30 June 2027.

Source: CRC art. 151.º-A, 233.º · Guia ISS 2026verified+ Google Calendar
May 2027
20
Thu
SS contribution for April 2027 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
June 2027
20
Sun
SS contribution for May 2027 pay
Falls on a non-working day — handle it by Friday 18 June.

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
30
Wed
IRS for 2026: last day file

File Modelo 3 with Anexo B (and the annual Anexo SS).

If you miss it: fine under RGIT. This deadline does not move to the next working day.

Source: CIRS art. 60.º · CRC art. 152.ºverified+ Google Calendar
July 2027
20
Tue
IRS advance payment pay

Only if AT sends you the document (about a month ahead). Under €50 is not paid.

If you miss it: interest.

Source: CIRS art. 102.ºverified+ Google Calendar
20
Tue
SS contribution for June 2027 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
31
Sat
Quarterly Social Security declaration file
Falls on a non-working day — handle it by Friday 30 July.

Declare your income for Q2 2027 in Segurança Social Direta.

If you miss it: fine of €50–250 and SS sets the minimum €20 contribution. You can still file late until 30 September 2027.

Source: CRC art. 151.º-A, 233.º · Guia ISS 2026verified+ Google Calendar
August 2027
20
Fri
SS contribution for July 2027 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
31
Tue
IRS payment for 2026 pay

If the assessment shows tax due, pay by this date.

If you miss it: interest and enforced collection.

Source: CIRS art. 77.º, 97.ºverified+ Google Calendar
September 2027
20
Mon
IRS advance payment pay

Only if AT sends you the document (about a month ahead). Under €50 is not paid.

If you miss it: interest.

Source: CIRS art. 102.ºverified+ Google Calendar
20
Mon
SS contribution for August 2027 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar
October 2027
20
Wed
SS contribution for September 2027 pay

Pay between the 10th and the 20th. Amount in Segurança Social Direta.

If you miss it: late interest; after 30 days a serious offence (€300–1,200).

Source: CRC art. 155.º, 168.ºverified+ Google Calendar

Rules that always apply

Line on your recibo verified

While income stays under €15,000, write on the recibo: Sem retenção, nos termos do n.º 1 do artigo 101.º-B do Código do IRS. Without it, the company withholds 23%.

Source: CIRS art. 101.º-B

EU clients: recapitulative statement to confirm

After the 2025 changes the rule is ambiguous for the art. 53 regime. Confirm with an accountant or AT.

Source: RITI · DL 35/2025

Invoice everything verified

Fatura-recibo on the day of payment; fatura by the 5th working day; EU services by the 15th of the next month. Advances included.

Source: CIRS art. 115.º · CIVA art. 36.º

Work accident insurance verified

Mandatory while the activity is open.

Source: DL 159/99

Changes and closing verified

Changes: 15 days. Closing the activity: 30 days.

Source: CIVA art. 32.º, 33.º

Prazos reminds and explains; it does not give advice. The decision is yours. Dates checked on 20 October 2026 against official sources (CRC, ISS Practical Guide, CIRS, CIVA). No account, no ads: your answers stay on this device only.

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