AT Fines
Multas AT · AT Fines (Tax Authority Penalties)
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Financial penalties (coimas) issued by the Portuguese tax authority (AT) for late or missing tax filings, undeclared income, or invoicing violations. Governed by RGIT; voluntary disclosure before AT notifies you significantly reduces the penalty.
The Autoridade Tributária e Aduaneira (AT) can issue financial penalties, called coimas, for a range of compliance failures. These are counter-ordination fines governed by the Regime Geral das Infrações Tributárias (RGIT), and they apply to solo entrepreneurs and freelancers just as they do to any other taxpayer.
Knowing when fines apply, what the amounts look like, and how voluntary disclosure changes the outcome is more useful than avoiding the topic entirely.
What AT can fine you for
Late or missing IRS filing
The IRS Modelo 3 declaration runs from 1 April to 30 June each year. Filing after the 30 June deadline is an automatic infraction under RGIT Art. 114. The fine is assessed per declaration period, not per individual error.
Late VAT filings
VAT-registered freelancers submit a Declaração Periódica monthly (above €650,000 annual turnover) or quarterly. Missing a deadline triggers a counter-ordination fine plus interest charges (juros compensatórios) on any unpaid VAT, running from the original due date under Art. 35 LGT.
Missing Social Security declarations
Self-employed people submit a Declaração Trimestral every three months to Social Security (Segurança Social). Missing this sits outside RGIT but follows similar counter-ordination rules under Social Security legislation. The AT and Social Security systems share taxpayer data.
Invoicing outside certified software
Since Portaria 363/2010, businesses above certain turnover thresholds must issue invoices through AT-certified software (with ATCUD and QR codes). Issuing invoices without certified software when required is a separate infraction category under RGIT. PDF invoices without AT-certified generation are non-compliant even if they look correct.
Undeclared or under-reported income
If eFatura data, withholding declarations from clients, or Social Security records show income that does not appear in your Modelo 3, AT can issue a correction assessment (liquidação adicional) with a fine attached. This category carries higher potential penalties than a late-filing infraction.
Fine ranges under RGIT
For most counter-ordinations by individuals, the range runs from approximately €50 (minimum for natural persons) to around €3,750 per infraction. The exact figure under RGIT depends on:
- Whether the failure was negligent (culpa) or intentional (dolo): intentional infractions carry higher penalties
- Your gross income for the period in question
- Whether you regularised voluntarily before AT contacted you
Interest charges on unpaid tax are separate from the coima and accrue from the filing deadline, not from the notification date. On top of the fine and interest, persistent non-compliance can escalate to an AT inspection (inspeção tributária).
Voluntary regularisation: the reduction mechanism
Filing late is not the same as being caught filing late. RGIT Art. 29 explicitly provides for penalty reductions when a taxpayer regularises spontaneously, before being notified by AT. The reduction is significant and the principle is consistent across infraction types.
In practice: if you missed the June IRS deadline and file your Modelo 3 in August without any AT prompt, the fine will be substantially lower than if you had waited for AT to send a correction notice. The window matters. AT's automated cross-referencing of eFatura and withholding data runs routinely, not only during inspections, so the gap between "missed deadline" and "AT notification" can close quickly.
Pay any owed tax at the same time as the late filing. Regularising the return without settling the tax balance leaves the interest clock running.
How AT discovers missed filings
AT cross-references three data sources continuously, not only during audits:
eFatura: Invoices issued through certified software feed into eFatura linked to your NIF. AT has a record of your billable income throughout the year. If you issued invoices totalling €30,000 but declared €20,000 in your Modelo 3, the gap is visible.
Withholding declarations: Portuguese clients are legally required to report the amounts they withheld from payments to you (retenção na fonte). These declarations land at AT independently of your own return. If a client declared withholding on payments to your NIF that don't appear in your income declaration, the system flags it.
Social Security: Quarterly declarations and contribution records document your active business periods. An active Social Security record alongside a missing Modelo 3 is a routine flag.
These three data sets are matched automatically. The AT letter that arrives after a discrepancy is typically a notice to regularise, not an immediate fine. But ignoring it converts a fixable situation into a more expensive one.
Cross-references
Frequently asked questions
What is the fine for late IRS filing in Portugal?
The fine (coima) for missing the Modelo 3 IRS deadline ranges from roughly €50 to €3,750 for individuals, under RGIT Art. 114. The exact amount depends on the length of the delay, your gross income, and whether the omission was negligent or intentional. Filing voluntarily before AT notifies you of an inspection reduces the fine significantly under RGIT Art. 29.
Can I file late and avoid a fine in Portugal?
Filing late does not eliminate the fine, but voluntary regularisation before AT notifies you substantially reduces it. Under RGIT Art. 29, spontaneous disclosure before being contacted by the tax authority results in a lower penalty than if AT initiates the correction. The sooner you file and pay any owed tax, the smaller the outcome. Waiting for AT to find the error is always more expensive.
What happens if I miss the VAT deadline in Portugal?
Missing a Declaração Periódica deadline is a counter-ordination (contraordenação) under RGIT with a fine range similar to IRS late filing. On top of the fine, interest charges (juros compensatórios, Art. 35 LGT) accrue on any unpaid VAT from the original due date. Missing multiple consecutive periods compounds the exposure, and the AT VAT systems flag repeated non-compliance automatically.
What are AT's fines for freelancers in Portugal?
Freelancers on the simplified regime face fines primarily for: late Modelo 3 IRS filing, missing or late quarterly Social Security declarations, late or missing Declaração Periódica if VAT-registered, and issuing invoices outside AT-certified software when required. Each category carries its own fine range under RGIT or Social Security regulations. The certified-invoicing obligation (Portaria 363/2010) adds a separate penalty category that many expat freelancers do not anticipate.
Does the AT fine automatically or only after an audit?
Both. For late filings, AT systems automatically flag missing submissions by cross-referencing deadlines. A missing Modelo 3 is visible in the system the day after the deadline. For undeclared or under-reported income, AT cross-checks eFatura invoice data, withholding declarations from your clients, and Social Security records against your filed return. Discrepancies trigger a review that can lead to a correction and a fine. Late-filing notifications are more routine; a discrepancy between eFatura income and declared income is more serious.
Related terms
The official Portuguese personal income tax return form. Filed annually between April and June for the previous year's income. Consists of a cover page (Rosto) plus annexes based on your income sources.
Retenção na FonteWithholding TaxIncome tax withheld at the source by Portuguese businesses when they pay a solo entrepreneur for services, the client keeps a percentage (23% standard since 2025) and sends it directly to the tax authority.
Trabalhador IndependenteSelf-Employed WorkerThe Portuguese term for an independent worker or sole entrepreneur, the equivalent of a freelancer or sole trader in other countries.
e-FaturaElectronic Invoice SystemPortugal's electronic invoice system that automatically tracks purchases linked to your NIF. Used for tax deductions: if your NIF isn't on the receipt, the expense doesn't exist for tax purposes.
Declaração TrimestralQuarterly DeclarationThe quarterly income report that solo entrepreneurs file with Social Security (Segurança Social) to calculate their monthly contributions for the following quarter.