When you're preparing an R&D tax relief claim, the focus is usually on the numbers.
How much did we spend? What can we include?
But before HMRC even looks at that, there's a more immediate question:
"Have we clearly explained what we actually did?"
That's where the Additional Information Form (AIF) comes in.
What Is the AIF?
It's a mandatory form that sits alongside your R&D claim.
You submit it before or at the same time as your Corporation Tax return, and without it, the claim simply won't be processed.
But in practice, it's more than just a form. It's your first impression.
What Does HMRC Expect to See?
The AIF isn't about writing everything you did.
It's about explaining the right things clearly.
That usually means:
- What technical uncertainty you were trying to resolve
- What work you actually carried out to address it
- Why that work wasn't straightforward
- Who was involved in the process
If those points aren't clear, it doesn't matter how strong the underlying work was.
Where Claims Often Go Wrong
Most issues with the AIF don't come from eligibility.
They come from how the story is told.
We often see:
- Descriptions that are too high-level to understand
- Activities listed without explaining the challenge behind them
- Generic wording that could apply to any business
- A disconnect between the narrative and the costs being claimed
None of these mean the claim is wrong. But they do make it harder to trust.
Why It Matters
HMRC now uses the AIF as an early risk filter.
In other words, this is where your claim is assessed before anyone gets into the detail. If it reads clearly and ties together, the process is usually smoother.
If it doesn't, that's when questions start.
A Better Way to Approach It
The way we see it at Optimyze, instead of treating the AIF as a form to complete at the end, treat it as the foundation of the claim.
Start with:
- What problem were we trying to solve?
- What made it technically uncertain?
- What did we actually do to figure it out?
If you can answer those clearly, everything else tends to follow.
The AIF isn't just admin. It's where you show that your claim makes sense.
If you're preparing an R&D claim and want a second pair of eyes on your AIF before submission, we're happy to take a look.
