The Immediate Information Supply System (SII) is a VAT management system implemented in Spain that requires the immediate electronic transmission of invoicing records to the Spanish Tax Agency (AEAT). Its primary objective is to improve tax oversight and reduce tax fraud through near real-time updating of fiscal information. Companies must submit the data from their issued and received invoices within four working days.
Is the SII truly effective and efficient?
Advances in technology have created a way for businesses and the Spanish Tax Authority to remain connected through digitalisation. The SII represents a reform of the current VAT management system that has been in place since 2017. It was introduced to enable more effective tax monitoring and to provide better support to taxpayers.
VAT is today managed on the basis of real-time information provided by taxable persons, together with other information obtained by the Spanish Tax Agency (AEAT) through the submission of VAT returns. The overarching aim is to combat tax fraud.
Who is required to file and pay VAT?
Businesses and individuals subject to the tax are responsible for declaring and paying it by means of a monthly sworn declaration, which must also be reflected in their accounting records. End consumers are not required to submit any documentation; only those who are registered and liable for this tax — that is, businesses or individuals within its scope — are obliged to do so.
Who must submit information through the SII?
- Businesses enrolled in the REDEME (Monthly VAT Refund Register).
- Large companies (those with an annual turnover of more than €6 million).
- VAT Groups, referring to REGE (Special Group of Entities Scheme) .
- Those who voluntarily choose to be governed by it, with the obligation to remain enrolled for at least the full fiscal year.
What are the requirements to register for the SII?
To join the SII, you must apply by completing Form 036 during November of the year immediately preceding the year in which it is to take effect. Boxes 143 and 532 must be completed; the registration does not come into force until the beginning of the following financial year.
The other — and more effective — option is to register at the start of the business activity.
The second option is the quickest and the most advisable.
Can you deregister from the SII?
To withdraw from the scheme, you must again submit Form 036 (the census declaration) in November for the withdrawal to take effect the following year.
If no withdrawal is requested, the option will be deemed to have been renewed automatically.
Entities enrolled in the SII must manage their records through the electronic portal of the Spanish Tax Agency (AEAT), by electronically supplying their invoicing records. The most important information in the system consists of the VAT Record Books:
· Issued Invoices Record Book
· Received Invoices Record Book
· Intra-EU Transactions Record Book
· Investment Goods Record Book
To this end, all relevant details must be submitted to the Spanish Tax Agency (AEAT) (Spanish Tax Agency), which will be used to build the VAT records in real time.
Submissions are made via Web Services based on the exchange of XML (Extensible Markup Language) messages — a set of rules that enables documents to be encoded in a standardised format.
How do I know if I am registered with the SII?
To find out whether you are registered with the SII, you can visit this page, go to the Tax Status menu and select the option Check third-party tax status.
This can be checked online without needing to visit an SII office in person.
Is the SII system worthwhile?
The SII system has its advantages, though in some cases there are also drawbacks:
Advantages of the Immediate Supply of Information (SII):
- Reduction in formal reporting obligations, as forms 347, 340 and 390 no longer need to be filed.
- Access to tax data. A declared and validated record book will be available through the online portal.
- Full access to invoice information included in the VAT ledger of clients and suppliers subject to the SII.
- Having all the information to hand makes it easier to prepare the VAT self-assessment return.
- A 10-day extension to the deadline for filing and paying periodic VAT self-assessment returns.
- Faster processing of refunds (near real-time information and greater detail on transactions).
- Shorter audit timescales, for the reasons set out above.
- Reduced information requirements, aimed at requesting invoices or data.
- Modernisation and standardisation of the way VAT record books are maintained.
Drawbacks of the Immediate Supply of Information System:
- A greater administrative burden for the company
- The need to train administrative staff on how to use it.
- Tight deadlines for submitting data.
- It entails a higher level of tax scrutiny.
- The need for software compatible with the Spanish Tax Agency (AEAT) platform.
Contact us and we will help you navigate these challenges:
When must SII records be submitted?
Invoicing records must be submitted to Spanish Tax Agency (AEAT):
1 January to 30 June, and the second half of the year runs from 1 July to 31 December
Records must be submitted to the Spanish Tax Agency (AEAT) electronic portal between 1 July and 31 December.
Check the tax calendar so you don't miss any filing deadlines throughout the year.
Invoices issued
The information must be submitted within four calendar days of the date the document is issued.
Where invoices are issued by the recipient or by a third party, this deadline is extended to eight calendar days.
In all cases, the information must be submitted no later than the 16th day of the month following the month in which the tax became chargeable in respect of the transaction being recorded.
Invoices received
The information must be submitted in the same way as for invoices issued — within four calendar days of the date on which the invoice is recorded in the accounting system.
This must always be before the 16th day of the month following the settlement period in which the relevant transactions were included.
For import transactions, the four-calendar-day period runs from the date on which the document showing the VAT amount assessed by customs is recorded in the accounting system.
To find out more about mandatory e-invoicing, visit this link
Intra-EU transactions
For intra-EU transactions, the deadline is four calendar days from the moment the dispatch or transport begins, or from the moment the relevant goods are received.
Capital goods
For capital goods, the data must be submitted within the filing deadline for the last annual settlement period, that is, by 30 January.
How can I check whether I have outstanding debts in the SII?
You can check directly on the Spanish Tax Agency (AEAT) website by navigating to Online Services, then selecting the Infringements, Payment Orders and Conditions option. You can log in using your Tax PIN (Clave Tributaria) or your unified digital identity (Clave única). A drop-down menu will display all the relevant taxpayer information, and you also have the option to search for specific items.
If you have any questions or require clarification, please do not hesitate to contact our tax and accounting advisory team in Barcelona.
