While value-added tax (VAT) is a common tax across the European Union, the rates and management of VAT differ significantly between member countries. In recent years, the EU has worked to harmonize certain VAT aspects across Europe, including the VAT One Stop Shop (VAT OSS). This system allows businesses’ registration for VAT in one member country to be valid throughout the EU. This initiative has also prompted many countries to introduce electronic invoicing requirements for businesses.

As part of this effort to ensure transparency in transactions and simplify the transmission of tax data, Spain introduced a new electronic filing system aimed at businesses called the Immediate Supply of Information (“Suministro Inmediato de Información,” or SII) in 2017, following the approval of Royal Decree 596/2016. In this article, we will outline the new system’s benefits, the deadlines for submitting the necessary documentation, and other important details about the SII.

What’s in this article?

• What is SII and what does it do?
  
• What are the key advantages of SII?
  
• What are the deadlines for filing SII?
  
• Which businesses must submit information through SII?
  
• How is the information submitted?
  

What is SII and what does it do?

SII is a system for managing VAT electronically. The Agencia Tributaria (AEAT, or the Spanish Tax Agency in English) developed this method to prevent fraud and simplify the submission of VAT record books. These books document the operations related to business activities, such as issued and received invoices, investment goods, and certain intracommunity transactions. The goal is to ensure accurate and transparent VAT collection.

Business and VAT information from invoices and other accounting documents that make up these books are submitted through the AEAT online portal.

What are the key advantages of SII?

SII offers several advantages to individuals and legal entities compared to the traditional VAT return system.

• VAT management is faster and simpler: This is largely because SII eliminates the need to file the informative declaration on record books (Form 340), the annual statement of transactions with third parties (Form 347), and the annual VAT summary (Form 390).
  
• Data is transmitted in real time: This allows the Agencia Tributaria to function more efficiently. The primary benefit for companies in Spain is the faster processing of VAT refunds, as the AEAT can validate the information shortly after receiving it.
  
• Data submitted through SII is more accessible: Businesses can now easily consult their tax information online.
  
• Businesses have a longer time to file: They have 30 days to file their VAT self-assessment online through SII, which is 10 days longer than the monthly filing deadline.
  

Aside from all these benefits for businesses, there’s a significant advantage for the Agencia Tributaria: SII greatly reduces tax fraud.

Before the implementation of SII, filling out numerous forms often led to frequent manual errors. While the number of errors has decreased since SII removed some filing requirements, a tool such as Stripe Tax can further simplify your tax obligations and help reduce your workload.

Stripe Tax automates VAT calculation and collection (including international equivalents such as US sales tax) for transactions in over 50 countries. It also monitors your tax obligations and alerts you if you exceed reporting thresholds in any jurisdiction where you sell your products and services. Additionally, Stripe Tax is regularly updated to reflect tax legislative changes in all the countries where it operates, ensuring you always apply the correct tax rate. We recommend checking the list of excluded territories.

What are the deadlines for filing SII?

The deadlines for SII filing vary depending on the information submitted:

• Issued invoices: You have a maximum of four calendar days from the date the invoices are issued to file with SII. If the recipient or an authorized third party issues them, this period is extended to eight days. Regardless of the situation, the SII must be submitted by the 16th day of the month after the month in which the VAT on the transactions was accrued.
  
• Received invoices: All received invoices must be submitted through SII within four calendar days of being recorded in the accounting system and by the 16th day of the month following the month that the VAT transaction occurred. There are no exceptions to extending the deadline.
  
• Intracommunity transactions: The period starts four calendar days from when the shipping or transportation of the acquired goods begins.
  
• Investment goods: This must be submitted within the deadline for settling the last tax period of the year, which is January 30 at the latest.
  

For any uncertainties, you can use the SII deadline calculator available on the AEAT website.

Note: While the Agencia Tributaria documentation refers to “calendar days,” it later clarifies that weekends and national holidays are not included.

Which businesses must submit information through SII?

SII is mandatory for some businesses and voluntary for others. Even if they are not required to use the electronic VAT management system, some businesses voluntarily do so to benefit from the advantages mentioned earlier. To either start using SII voluntarily or to opt out of its voluntary use, you must submit Form 036 in November. This ensures that your decision will take effect the following year.

As previously mentioned, certain businesses must always use SII. While quarterly VAT returns are the most common for companies, individuals or legal entities required to file monthly self-assessments must also use this system. The following businesses are required to use SII:

• Large companies with an annual turnover of more than €6 million
  
• Businesses that fall under the special system of the group of entities (“Régimen especial del grupo de entidades,” or REGE)
  
• Businesses that fall under the monthly VAT refund system (“Régimen de devolución mensual,” or REDEME)
  

Note: If you are an individual or legal entity not required to use the SII but choose to do so, you can still make your VAT settlements quarterly.

How is the information submitted?

Submitting information through the SII is straightforward, especially with the help of the virtual assistant provided by the Agencia Tributaria. First, note that you don’t need to send all your invoices to them. Instead, you only need to submit the specific invoicing record fields outlined in Ministerial Order HFP/417/2017. These are the most important and common fields:

• All the information in the book of invoices issued: Include the number or series, date of issue, date of transaction, name and surname, company name, recipient’s tax identification number (NIF), taxable base, VAT rate, and charge from the book.
  
• Type of invoice: Specify whether it is complete or simplified.
  
• Identification: Use this field only for rectifications.
  
• Description: Describe the content of the transactions performed.
  
• Rectification invoices: Identify these types of invoices by specifying what has been changed or by referencing the originals that were corrected.
  
• Period: The date on which the invoice transactions were settled.
  
• Transaction not subject to VAT: If transactions not subject to VAT have been made, indicate them here.
  

Article 7 of the mentioned Ministerial Order provides a detailed breakdown of each step involved. To summarize, here are the two ways to send information through the SII:

• Exchange of information in XML format: This method is intended for individuals or legal entities that handle a high volume of transactions. Web services can handle electronic messages, but they must not exceed a certain limit of invoicing records. The XML file must match both the ledger and transaction type. For more technical details, please refer to the complete information on the AEAT website.
  
• Web form: This process is suitable for individuals or legal entities with a low volume of transactions and for those who need to submit specific invoice records individually. The web form enables you to submit information on an individual basis.
  

No matter which method you choose, once you submit the information, each VAT record book will be compiled almost in real time. To achieve this, the common header must include the information of the record book holder, along with details about the fiscal year and the period during which the transactions are documented. Aside from the header, there should also be a block that details the contents of all the invoices in your XML file.

In short, sending the data through the SII is straightforward, regardless of your approach. If you have questions, you can consult the AEAT frequently asked questions about SII page.