BlogTax Basics Amending tax returns: the R&D Law's retroactivity explained
One advantage of the notice of intent is that the R&D Law credit applies retroactively. But that retroactivity has a practical consequence: you may need to amend prior years’ tax returns.
Why you need to amend
With a notice of intent, a company can start spending before the project is certified. But the process is long:
- Up to 18 months to submit the formal certification application.
- Up to 180 calendar days for Corfo to certify.
By then, the company has already filed taxes for one or more years in which it incurred project costs, without being able to use the 35% credit yet.
That’s why the law says that, to apply the credit, the taxpayer must calculate it for each year in which the spending occurred, amending the corresponding returns.
Refund of overpaid tax
If amending shows the company paid more tax than it should have, it can request a refund under Article 126 of the Tax Code, adjusted for inflation.
An important detail from SII Circular No. 19: the 3-year window set by Article 126 runs from the date of Corfo’s certification, which is the event that gives rise to the right.
A simplified example
A company sends its notice of intent in March 2025 and spends on R&D during 2025 and 2026. Corfo certifies the project in 2027.
| Step | What happens |
|---|---|
| 2026 return (2025 financial year) | Deducts the 65% as an expense, but can’t use the credit yet |
| 2027: certification | The right to the 35% credit on certified spending arises |
| After certification | Amends the 2025 financial year return to include the credit |
| If it overpaid | Requests the inflation-adjusted refund within 3 years of certification |
Illustrative example. Exact timings depend on each case.
The reverse case: when certification is revoked
Retroactivity also cuts the other way. If Corfo revokes certification because the company breached the certified terms or didn’t provide audit information, the company must amend its returns from the date of the breach and pay the difference with the applicable inflation adjustments, interest and surcharges. See After certification.
Recommendations
- Get your technical team and accountant working together from the start: project costs must be identifiable in each year’s accounts.
- Schedule the amendment as soon as you receive Corfo’s resolution.
- Keep all supporting documents: invoices, proof of payment and time records.
This article is for information only and is not tax advice. Sources: Law 20,241, SII Circular No. 19, Tax Code (arts. 57 and 126) and Corfo’s FAQ.