25 July 2026 · Seisly
What the Seisly blog covers
What we write about here: SEIS and EIS advance assurance, what HMRC looks for, and how to prepare an application that reads the way HMRC expects.
- SEIS
- EIS
- advance assurance
This is where we write about SEIS and EIS advance assurance: what it is, what HMRC actually looks for, and how to prepare an application that reads the way HMRC expects.
Most advance assurance applications are refused not because the company does not qualify, but because the application does not show that it does. The difference is in how the company, its trade and its use of the money are described. That is what we write about.
Where to start
If you are preparing an application now, three pieces cover the ground:
- The SEIS & EIS Playbook: the nine tests HMRC applies, the language patterns behind rejections and approvals, and a fully worked annotated application.
- Deciding how to file? Seisly vs SeedLegals and Seisly vs FounderCatalyst compare price, scope and turnaround, honestly.
- Not sure you qualify yet? The free eligibility check tests your company against the statutory conditions before you spend anything.
How we write it
Plain English, no jargon, and no promises about outcomes: advance assurance is HMRC’s decision, not ours. Where a point turns on a statutory figure or a rule that changes, we date it and link the source rather than leave you to guess.
Frequently asked questions
- Who writes the Seisly blog?
- The blog is written by the Seisly team, drawing on the experience of our founder, who started the UK’s first SEIS fund in 2012 and is a Chartered Tax Adviser and ICAEW Fellow.
- Is anything here tax advice?
- No. The blog is general guidance for founders preparing an SEIS or EIS application. It is not tax or legal advice for your specific circumstances. Where you need advice, we can refer you to a specialist firm through Seisly Advisers.