Can I get the Forschungszulage retroactively?

Summary

Process Overview

• 1Up to 4 years retroactively possible
• 2Advantage: Apply with actual data instead of planned figures
• 3Process: First BSFZ, then tax office/ELSTER
• 4After tax office submission: practically locked in

You can secure the Forschungszulage retroactively (public funding) for R&D (FuE) expenses from previous years—typically up to 4 years retroactively (the decisive factor is the applicable deadlines/assessment limitation periods per calendar year). The biggest practical advantage: you apply using actual ("as-is") data instead of uncertain planned figures. The process is: first BSFZ (technical certification), then the tax office/ELSTER (tax assessment). And crucial for real-world planning: Once the application has been submitted to the tax office, the outcome is effectively "locked in" — changes are not intended as a simple quick fix.

We explain the full step-by-step process (BSFZ → tax office) in detail here: Application Process Guide. In this post, we deliberately focus on the retroactive topic, strategy, and typical practical questions.

What does it actually mean to apply for the Forschungszulage retroactively?

"Retroactively" means: you can still claim R&D (FuE) expenses from years that have already been completed—up to four years retroactively. This is exactly what makes the Forschungszulage (public funding) so attractive for many companies that:

• only discovered the funding late,
• initially avoided it due to application uncertainty,
• or only now have the resources to properly prepare documentation and costs.

The key idea: retroactivity is not a "last resort," but a deliberately built-in advantage—especially for teams that have already been doing serious development work in the past.

Who can apply for the Forschungszulage retroactively?

Any company taxable in Germany (including sole proprietors) that carried out eligible R&D (FuE) projects in the relevant period. Profit or paying taxes in the expense year is not a requirement—if the allowance exceeds the assessed tax, it is paid out.

Eligible are projects in basic research, industrial research, or (most commonly) experimental development. Projects must be describable in technical terms: state of the art, measurable objective, technical uncertainty, and a systematic approach. A common mistake: wording that is too "business-heavy." Personnel costs are usually the biggest lever; R&D shares must be plausible. BSFZ initially only checks plausibility; the detailed review happens at the tax office.

Important: The 4-year period is running—if you haven't used it for several years, you should now systematically identify the relevant projects before a year expires permanently.

You can find more information in our guide to the requirements: Requirements for the Forschungszulage

The real lever: applying retroactively means "winning with actual data"

Many people only know grant programs like this: apply upfront → report later → explain deviations. Exactly this "plan vs. reality" friction costs time, nerves, and in the worst case, funding money.

The Forschungszulage works differently—and retroactively, this advantage is strongest:

• You already know what was really built, tested, and discarded.
• You can describe the state of the art, target metrics, and risks concretely (instead of speculating).
• You know the real costs (personnel costs, contract research, and, where applicable, capital assets—depending on the period/rules).

From an expert perspective, this is why applying for the Forschungszulage retroactively is often more efficient than applying "on an ongoing basis": less estimating, less rework, less need for amendments.

Timing in practice: When does "applying for the Forschungszulage retroactively" make the most sense?

Instead of "as early as possible" (sounds good, but is too generic), the better practical question is:

1) How solid is your R&D case—and how good is your documentation?

Typical first-call situation:

• The biggest uncertainty is rarely "costs," but: Is this even R&D under the law?
• This can often be clarified quickly if you talk cleanly and technically through state of the art → technical goal → approach → risk.

Rule of thumb from practice:

• If it is clearly R&D, the application can be worthwhile even at mid-sized budgets (because preparing the application is relatively straightforward).
• If it's a borderline case (e.g., lots of product/feature work without a clear technical risk component), the potential amount should be substantially higher—because realistically you'll need more iterations in the technical narrative.

2) "Retroactive" does not mean: "wait until December"

Yes, the Forschungszulage (public funding) can be applied for retroactively—but: for older years, you need the technical certificate in time so the tax part can run cleanly. Especially when projects are far in the past, reworking documentation (tickets, commits, experiments, architecture decisions) does not get easier.

Practical recommendation:

• Often optimal is: 1–2 years retroactively + the current year.
• Then: catch up annually as long as the project continues.

This way you combine:

• high certainty through actual data,
• continuous funding,
• less risk of having to "creatively" reconstruct later.

BSFZ vs. tax office—what matters retroactively?

You'll find the full process in the Application Process Guide on dieforschungszulage.de. For the retroactive topic, this classification is enough:

• BSFZ (technical): checks whether the project is R&D—costs only for plausibility, not as detailed evidence.
• Tax office (tax via ELSTER): checks the actual expenses in detail (e.g., salaries, time tracking records, contracts, invoices) and determines the allowance.

Practical point that is especially important for retroactive applications:

When you apply retroactively, you typically want to process multiple years "in one go" cleanly. For that, the sequence must be right:

1. Get the technology/project certified cleanly (BSFZ).
2. Then have the years assessed for tax purposes (tax office/ELSTER).

Because: Once the application is filed with the tax office, that is not the moment for "oh, we'll just correct it quickly later." Plan so that what you submit to the tax office is truly "final."

Cost estimation in the BSFZ application: realistic, plausible—and strategically smart

A common misconception: "We must hit the costs exactly in the BSFZ application."

In practice:

• BSFZ checks plausibility (does it broadly fit the story, team size, and project type?).
• The detailed audit comes later at the tax office.

A proven practical strategy:

• Don't inflate it to the limit, but don't artificially understate it either.
• Estimate in a way that later deviations are more likely downward (so the tax office doesn't face the problem of having to "increase" amounts retroactively).

Here is a first cost estimate guide: Calculation of the Forschungszulage

What happens if costs or scope later deviate significantly?

Applying retroactively reduces deviations—but doesn't eliminate them, e.g., if you cover multiple years/project runtimes in the BSFZ application.

If it later turns out that:

• the expenses differ significantly from what was plausibilized, or
• the project is no longer essentially the same ("im Wesen"),

… then an amendment application with BSFZ may be required before the tax office can assess cleanly.

Rule to remember: First keep BSFZ consistent, then submit the tax office application "fixed."

How to start retroactively without losing time

1. Pull a retroactive project list: Which past projects had real technical uncertainty?
2. Build the technical narrative: state of the art (with benchmarks) → target metrics → work packages → risk.
3. Structure costs roughly: personnel costs, contract research, and, where applicable, capital assets (depending on the period).
4. Prepare the BSFZ application (details in the Application Process Guide on dieforschungszulage.de).
5. After certification: file a tax office application per year via ELSTER with audit-ready evidence.

Do you still have questions about this topic?

We are happy to discuss your specific case in a free initial consultation. We'll find out in just a few minutes how much funding your company can receive.

Free ConsultationCall Now