Changes to the ATC’s Immediate Supply of Information (SII) System Starting October 1, 2025: Everything You Need to Know (and Why You Can Be at Ease)
Starting October 1, 2025, the Canary Islands Tax Agency (Agencia Tributaria Canaria – ATC) will implement a series of important changes to the Immediate Supply of Information (SII) system
At Grupo Dynasoft, we want to clearly explain what this update involves and, most importantly, reassure you that we are fully up to date with the current situation.
What do the SII changes consist of?
The ATC has announced a technical and regulatory evolution of the SII aimed at improving the traceability, control, and quality of electronically submitted tax data. Key updates include:
- New mandatory fields in the record books, particularly for transactions with tax implications.
- Additional validations for complex invoices, cash transactions exceeding €6,000, travel agencies, and capital goods.
- Inclusion of AIEM and special taxes: Starting in October, records must reflect not only IGIC but also AIEM (Arbitrio on Imports and Deliveries of Goods) and other applicable special taxes.
Who is affected by this update?
All companies, professionals, and entities operating within the Canary Islands’ tax jurisdiction that are subject (or required) to use the SII system with the Canary Islands Tax Agency. This includes, in particular, those under the monthly IGIC refund regime or that are part of large companies or VAT groups.
What does this mean for your business?
This update is not optional. As of October 1, businesses must:
- Adjust their management and accounting systems to comply with the new formats.
- Ensure proper classification of transactions according to the new ATC codes.
- Review internal processes to submit tax information within the required deadlines.
Thank You to Our Clients
Thanks to the collaboration of our clients, we are fully informed of this change. We are actively working on it and will keep you updated.
At Grupo Dynasoft, we want to make it clear that you are not facing this new scenario alone. Our commitment is to provide you with the best technology, the best support, and complete peace of mind so that you can stay focused on your business.
You can find more information at the following links:
Canary Islands Tax Agency
Technical Specifications Document
Functional Blocks
Validations and Errors Document
Compatibility Chart
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