Issuing invoices correctly is essential for any business in Portugal. In addition to being a legal requirement, invoicing ensures transparency in transactions and prevents potentially heavy fines. All sales of goods or services must be documented, even if the customer does not request an invoice.
In this guide you will find a clear explanation of:
- The types of invoicing documents available,
- The elements that must always be included,
- What to do when the client does not provide a Tax Identification Number (NIF),
- Recent fiscal requirements such as ATCUD and QR Code,
- Rules on language and currency,
- And the obligations to report invoices via SAF-T.
Types of Invoicing Documents
Each transaction may require a different document depending on its nature and timing. Knowing the types of invoicing documents is essential to understand which one should be used in each situation and to avoid errors that may lead to tax implications.
- Invoice: The main document for all sales or services. It records the transaction but does not prove payment.
- Receipt: Issued after payment, linked to the invoice.
- Invoice-Receipt: Combines invoice and receipt when payment is immediate. Commonly used by freelancers.
- Simplified Invoice: Used for low-value sales (up to 100 € for services or 1,000 € for goods) when payment is immediate. It does not require the client’s NIF unless requested.
- Credit Notes: Correct or cancel invoices.
- Delivery/Transport Notes: Documents that accompany goods in circulation or shipment to the customer.
Mandatory Elements of the Invoice
Issuing an invoice is not just writing the amount due. There are formal requirements that ensure the document has legal and tax validity. These elements identify the parties involved, the nature of the transaction, and the taxes owed.
- Supplier details: Name/legal designation, address, and Tax Identification Number (NIF).
- Client details: Name, address, and NIF (mandatory in B2B transactions and for B2C sales of ≥ 1,000 €).
- Transaction details: Goods/services, quantities, unit prices, and totals.
- Date of issue and sequential number (unique and continuous within each series).
- VAT rates and amounts applied, or legal reference for exemption.
- QR Code (mandatory since 2022).
- ATCUD (unique document code) (mandatory since 2023).
- Qualified digital signature: Required for electronic invoices sent to public entities. For other transactions (B2B or B2C), PDFs continue to be accepted as valid invoices without a signature, unless legislation states otherwise.
📌 Issuing an invoice is not just about writing the amount to be paid. There are formal requirements that ensure the document has legal and tax validity.
The Client’s NIF
The Tax Identification Number (NIF) is a central element in invoicing, but it is not always mandatory. The rules vary depending on the type of client, the transaction amount, and whether the client requests it.
- Individuals up to 1,000 €: The client may choose not to provide a NIF. The invoice may be issued in the name of “Final Consumer”.
- Individuals above 1,000 €: It is mandatory to collect name, address, and NIF.
- Whenever the client requests it: The NIF must always be included, regardless of the amount.
- Companies and freelancers: The NIF must always be included.
If the client requests the inclusion of the NIF after the invoice has been issued, the correct procedure is to issue a credit note and then a new invoice.
Other Fiscal Requirements
In addition to the basic invoice details, there are additional rules that guarantee uniformity and transparency in the Portuguese tax system. These may seem minor, but they are essential for compliance and to avoid fines during inspections.
- Language: Invoices must be in Portuguese, but they may be bilingual. They are also accepted in a foreign language provided that a translation into Portuguese can be made available if requested.
- Currency: Invoicing in another currency (e.g. USD, GBP) is possible, but the values must also be converted and presented in euros, including the VAT amount.
- Numbering and series: Each invoice series must be communicated to the Tax Authority and receive a validation code to generate the ATCUD.
- Certified software: Most taxpayers are required to issue invoices through software certified by the Tax Authority.
Communication of Invoicing Documents to the Tax Authority
Invoicing documents must be communicated electronically to the Tax Authority. This can be done directly via the e-Fatura portal or through a webservice.
Evolution of reporting deadlines
Over the years, the deadlines for reporting invoices to the Tax Authority have been shortened to strengthen control and speed in collecting tax data. Knowing this timeline helps to understand the current strict requirements.
- Until 2016: 25th day of the following month.
- 2017–2018: 20th day of the following month.
- 2019: 15th day of the following month.
- 2020–2022: 12th day of the following month.
- • Since 2023: 5th day of the following month (with tolerance until the 8th only in 2023).
Communication of no invoicing:
Since January 2023, it has also been mandatory to declare months in which no invoices were issued.
Conclusion
Complying with all these rules is essential to avoid fines, keep the business in good standing, and reinforce trust with clients and partners. Issuing invoices correctly is part of sound business management and a healthy relationship with the Tax Authority.
Do you want to ensure you are complying with all invoicing rules without mistakes?
Yes, for all sales of goods or services, even low-value ones.
Only in very specific cases. As a rule, certified software must be used.
Yes, provided that a Portuguese translation can be provided if requested, and all values must also be shown in euros.
A fine applies. The current deadline is the 5th day of the following month.
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