Multiple founders: e.g. 4 founders at 25% each
Later joiners: new founders can qualify if ≤30% ownership
Asymmetric setup: original founder at 100%, new SEIS founders ≤30% each
Early investor mix: e.g. 3 founders at 30% + 10% external investor
Foreign ownership: non-UK founder ownership doesn't block UK founders (≤30% each)

Why it matters

Founder SEIS requires careful setup and slightly higher upfront cost - but if your startup succeeds, it could mean millions saved in CGT on exit.

Let's consider two founders, both investing £100,000 in their business. Founder A uses SEIS, while Founder B does not. They both exit for £20m.

Founder A: Investing under SEIS

What happens at each stage when SEIS is in place.

Income Tax Relief:

£50,000 (50%) of the investment is claimed as income tax relief.

Exits for £20M:

No Capital Gains Tax payable after three years.

Founder Passes Away:

Shares held for over two years qualify for 100% IHT relief under BPR. From April 2026: 100% relief on the first £1m and 50% on the excess, creating a 20% IHT rate above £1m.

Startup Fails:

Founder A can claim 22% loss relief (depending upon the founder's tax position).

Founder B: Investing without SEIS

What happens at each stage when SEIS is not used.

Income Tax Relief:

None.

Exits for £20M:

Up to £1m gains taxed at 18% Capital Gains Tax under BADR. >£1m gains 24% Capital Gains Tax charged.

Founder Passes Away:

Shares held for over two years qualify for 100% IHT relief under BPR. From April 2026: 100% relief on the first £1m and 50% on the excess, creating a 20% IHT rate above £1m.

Startup Fails:

None.

What's included

We handle the full process to ensure your founder SEIS setup is compliant and effective:

End-to-end guidance and structuring support
Review of shareholder/subscriber structure (NewCo)
Full SEIS compliance management & certificates
Preparation and submission of Advance Assurance
Support setting up an arm's length funding round post-approval

Simple, transparent pricing

Founder SEIS isn't a separate purchase. It's included whenever you buy a funding round or start a subscription. No add-ons, no extras.

Full priced round

£1,450 +VAT · One-time fee

Founder SEIS structuring advice
Full SEIS compliance & certificates
Advance Assurance submission
Support through a properly priced funding round
Membership in the FounderCatalyst community

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Launchpad Subscription

£995 +VAT / year

Or mix and match ASAs, Agile and Priced rounds, as often as you like.

Unlimited ASA, Agile & Priced rounds
£100k fundraising cap
SEIS/EIS advance assurance
SEIS/EIS compliance and certificates
Unlimited expert support

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Core Subscription

£1,995 +VAT / year

Everything in Launchpad, with no fundraising cap.

Unlimited ASA, Agile & Priced rounds
No fundraising cap
SEIS/EIS advance assurance
SEIS/EIS compliance and certificates
Unlimited expert support

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Founder case study

Sam Simpson

Roc Technologies Ltd

Before co-founding FounderCatalyst, Sam used SEIS to invest in his own company as a director.

Grew Roc Technologies from £0 to £30m revenue in 4 years
Successfully exited to private equity
SEIS structure saved millions in CGT per founder

This experience led to the creation of FounderCatalyst.

Connect with Sam on LinkedIn

Get SEIS for investing in your own business

Ready to structure your founder investment properly? FounderCatalyst handles the complexity - so you can focus on building your company. No credit card required.

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