How to file your EIS and SEIS claims

Without a headache

If you've invested in an early-stage startup under the Enterprise Investment Scheme (EIS) or Seed Enterprise Investment Scheme (SEIS), you're entitled to claim generous tax reliefs. But first, you need to actually file the claim.

Whether you're new to the process or just want a smoother experience this time around, here’s a practical breakdown of how to submit your EIS or SEIS claim and make the most of your investment.

First Things First: What Is EIS and SEIS Tax Relief?

Let’s quickly recap what you’re claiming:

SEIS lets you claim back up to 50% of your investment (for up to £100,000 invested per year).
EIS offers up to 30% income tax relief (for up to £1 million invested, or £2 million if the business qualifies as knowledge-intensive).

Both schemes are designed to support innovative UK startups and reward investors with tax incentives in return.

Step 1

Wait for the Company to Get Their Compliance Certificate

Before you can make a claim, the company you've invested in needs to:

Be trading and meet all the qualifying criteria
Apply to HMRC for EIS/SEIS compliance
Receive their compliance certificate (Form SEIS3 or EIS3)

Once they’ve done that, they’ll send you a copy of your individual SEIS3 or EIS3 form. You can’t claim without this.

Step 2

Claiming Your Tax Relief

There are two ways to submit your claim, depending on how you file your Self Assessment:

If You Use Self Assessment Online:

Log in to your HMRC account.
Head to the “Tailor Your Return” section and select ‘Yes’ when asked if you’ve made any investments under EIS/SEIS.
Fill out the relevant section using the details from your SEIS3 or EIS3 form.

You’ll need to include:

Company name
Amount invested
Date of issue
HMRC reference number (from the form)

If You Submit by Paper:

Fill in the “Additional Information” section (usually box 10).
Write a short note detailing the investment, referencing the form.
Attach a copy of the SEIS3 or EIS3 to your return.

Top tip: If your claim is for a previous tax year, or you're not submitting a return, you can write directly to HMRC with your details and include the certificate.

Step 3

Watch Out for the Carry-Back Option

Did you know? Both EIS and SEIS let you carry back your tax relief to the previous tax year, so if you didn’t use your full allowance last year, you might be able to apply it there instead.

Just make sure to clearly indicate that you want to carry back the relief when filling in your return.

Step 4

Wait for Confirmation

HMRC will process your return and apply the tax relief.

If you’ve already paid your tax bill, you’ll likely get a rebate.

If not, your future tax owed will be reduced.

Final Thoughts

Claiming your EIS or SEIS relief is a powerful way to reduce your tax bill and support UK startups, but only if you follow the right steps.

If you're feeling unsure or have multiple investments to juggle, it may be worth speaking to your accountant to ensure everything is submitted correctly.

Still stuck? Feel free to reach out, we’re happy to point you in the right direction.