SEIS/EIS Compliance Checklist for UK Startups (2026)

SEIS and EIS are powerful fundraising tools for UK startups — they offer investors up to 50% (SEIS) or 30% (EIS) income tax relief on their investment, making your round significantly more attractive. But the tax relief only works if you meet HMRC's eligibility criteria and file the right paperwork correctly. Most delays and rejections are caused by avoidable documentation mistakes, not genuine eligibility problems. This checklist covers what you need to know and prepare.

SEIS vs. EIS: key differences

Phase 1: Eligibility prep (before raising)

Before approaching investors with SEIS/EIS eligibility, verify that your company actually qualifies. HMRC will reject claims retroactively if criteria aren't met.

• Company age: For SEIS, you must be within 3 years of your first commercial sale. For EIS, within 7 years (or 10 for knowledge-intensive companies doing significant R&D). The clock starts at first revenue, not incorporation.
• Trade type: Certain activities are excluded: property development, financial services, farming, running hotels/care homes, legal services, and others. Check the full HMRC excluded activities list — it catches more founders than expected.
• Gross assets: For SEIS, total gross assets must be under £350,000 immediately before the shares are issued. This includes cash, so if you've bootstrapped to £400k in the bank, you may not qualify for SEIS. For EIS, the threshold is £15 million.
• Employees: SEIS requires fewer than 25 full-time equivalents. EIS allows up to 250. Contractors counted as FTEs if they work exclusively for you.
• Independence: The company must not be controlled by another company. Subsidiaries of larger entities typically don't qualify.
• Use of funds: The money raised must be spent on qualifying business activities within 3 years (SEIS) or 2 years (EIS). Holding cash or using funds for non-qualifying purposes invalidates the relief.

Phase 2: Document readiness

HMRC's compliance check reviews your governance documents. Having these ready before you raise prevents delays after the money arrives.

Phase 3: The HMRC process

Advance assurance (optional but recommended)

Before you raise, you can apply to HMRC for advance assurance — a non-binding confirmation that your company appears to qualify. This takes 4–6 weeks and gives investors confidence that their tax relief will be approved. It's not mandatory, but experienced angel investors and syndicates often require it before committing.

The advance assurance application requires: a description of the trade, business plan, summary financials, details of the proposed share issue, and confirmation that all eligibility criteria are met.

Compliance statement (SEIS1/EIS1)

After the shares are issued and the money is received, you file a compliance statement with HMRC. This is the formal application for SEIS/EIS status. For SEIS, use form SEIS1. For EIS, use form EIS1. These forms must be filed online through HMRC's EIS/SEIS service.

Investor certificates (SEIS3/EIS3)

Once HMRC approves the compliance statement, they issue you certificates (SEIS3 or EIS3) — one per investor. You forward these to your investors, who use them to claim tax relief on their self-assessment tax returns. Delays in filing the compliance statement = delays in investors getting their tax relief = unhappy investors.

Common mistakes that cause rejections

• Misaligned dates: The date on the board resolution, the subscription agreement, the SH01 filing, and the bank receipt must be consistent. If your board resolution is dated after the share allotment, HMRC will flag it.
• Missing subscription agreements: Every investor needs a signed subscription agreement — not just a bank transfer confirmation. The agreement must specify the number of shares, price per share, and that the shares are being issued under SEIS/EIS.
• Share certificates not issued: These must be issued within 2 months of allotment. Many founders forget or delay this step.
• Companies House not updated: Your SH01 (return of allotment of shares) must be filed within 1 month. Your confirmation statement must be current. Any discrepancy between Companies House records and your HMRC filing triggers questions.
• Excluded activities not checked: A SaaS company is fine. A SaaS company that also does consulting might have a problem if the consulting revenue exceeds 20% of total revenue. HMRC looks at actual activities, not just what you call yourself.
• Investor connected to the company: An investor with over 30% of the shares (including associates) cannot claim SEIS/EIS relief. Watch for existing shareholders increasing their stake through a new round.

Founder workflow that prevents rework

1. Use approved templates for subscription agreements, board resolutions, and share certificates. This ensures consistent formatting and required fields across all investor documents.
2. Collect e-signatures in sequence: Board resolution first → subscription agreements → share certificates. This maintains the correct chronological record.
3. Auto-store signed copies with audit trails in your deal room. When HMRC requests supporting evidence, everything is accessible in one place.
4. Run a pre-filing checklist before submitting the SEIS1/EIS1: verify all dates align, all documents are signed, Companies House is up to date, and all investors have been correctly recorded.