SII is a VAT reporting system that is provide to transmit the invoice records to Spanish Tax Agency (AEAT – Agencia Estatal de Administración Tributaria) electronically. It has been used since 1 July, 2017.


SII is mandatory for these taxpayers;

  • Large entrepreneurs (turnover exceed of 6m EUR)
  • VAT Groups
  • Registered in the REDEME (Monthly VAT Refund register)


Invoices is not transmitted to the AEAT system. Only the following records must be sent;

  • Register Book of issued invoices.
  • Register Book of received invoices.
  • Register Book of investment goods.
  • Register Book of specific Intra-Community operations.

The taxpayers registered SII are exempt from form 347 (Annual Sales and Purchase Listings), form 340 (VAT ledgers return), form 390 (Annual summary VAT return) and VAT Records Books.


The taxpayers must send records details to Tax Agency system as XML file via web service.

Files are transmitted to AEAT;

  • Within 4 work days after invoice issued date for outbound invoices,
  • Within 4 work days after invoices’ accounting date or the single custom document for inbound invoices.

The delay in sending records will result in a proportional pecuniary fine of 0.5 per cent of the invoice amount in the record. It can be minimum €300 and maximum €6.000.


With Netle Yazılım –Global e-Transformation infrastructure, documents and standard audit files which are congruent with SII requirements and legal mandatories can be prepared. Netle SII solution which is created with electronic management tools or user interface by the scope of specific rules creates documents automatically according to public institution. Netle SII solution completes the legal signing process of documents (if necessary) and archives them within the boundaries of the European Union according to customer requirements.

Throughout the entire process, the Netle Tick Tock System (NTTS) support platform provides 24/7 support for questions / problems.