---
title: "SII and Spanish Tax Agency (AEAT) integration | Kyros"
description: "We connect your software to the Spanish Tax Agency: SII, corporate tax forms 200 and 202 and automatic filings, with rejection handling. In production."
url: "https://kyros-software.com/en/aeat-integration"
locale: "en"
site: "Kyros"
---

# AEAT and SII integration

> We connect your invoicing or accounting app to the Spanish Tax Agency (AEAT) so filings go out on their own: SII on time, corporate tax ready to file and rejections handled without manual work.

## What's included

- Immediate Supply of Information (SII): invoices grouped and sent to the AEAT within the legal deadline.
- Automatic handling of invoices the Tax Agency rejects.
- Corporate tax (forms 200 and 202): a step-by-step assistant fed by the accounting data.
- The official AEAT file, ready to submit.
- All of it as a module inside your app, no new tool to learn.

## Already in production

We built two tax modules for an invoicing application:

- VAT reporting to the Tax Agency (SII): groups invoices, sends them within the legal deadline and handles rejected ones on its own.
- Corporate tax: pulls data from the accounting, detects the applicable tax items and generates the official file for forms 200 and 202.

## How we work

- A clear estimate before we start, no surprises.
- Phased deliveries: you see progress early and always know where the project stands.
- Our own code, documented and reviewed: any team can pick it up.
- Deployment, monitoring and support once it's live.

## Common questions

### Can you add SII to software we already have?

Yes. We built it as a module inside an existing invoicing app: it hooks into its invoices and takes care of filings and rejections.

### Which AEAT forms have you automated?

VAT Immediate Supply of Information and corporate tax, forms 200 and 202. If you need another form, we'll look into it.

### Do you work with accounting and advisory firms?

Yes. We built the day-to-day portal of a network of advisory firms: internal communication, documents, training and management.

## Tell us about your project

We reply within 24-48 business hours with a proposal and an estimate, no strings attached.

Contact form: https://kyros-software.com/en#contacto

---

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