SEIS advance assurance

SEIS Advance Assurance: What It Is and How to Get It

SEIS advance assurance is a written confirmation from HMRC that a proposed share issue is likely to qualify for relief under the Seed Enterprise Investment Scheme. It is voluntary and it is not a guarantee, but most angel investors and funds expect to see it before they commit, because it removes the risk that the tax reliefs they are counting on will be refused. This guide explains what advance assurance covers, who qualifies, how to apply, and how long it takes.

What is SEIS advance assurance?

Advance assurance is HMRC's view, given before you raise, that your company, your shares, and your planned use of funds meet the SEIS qualifying conditions. It is separate from the compliance stage that comes later: advance assurance happens before you issue shares, while the SEIS1 compliance statement and the SEIS3 certificates investors use to claim relief come after the shares are issued. Advance assurance is the document investors ask for at the point they are deciding whether to back you.

Why investors expect advance assurance

For an angel or a fund, SEIS is worth 50% income tax relief on what they put in, plus capital gains tax exemption on the upside. That only materialises if HMRC agrees the company qualifies. Advance assurance is HMRC signalling, in advance, that it is likely to. Without it, an investor is relying on your word that the relief will come through. Many funds make advance assurance a condition of investing, and even where they do not, having it in hand makes a round materially easier to close.

SEIS qualifying conditions: does your company qualify?

To qualify for SEIS, broadly, your company must:

• have been trading for less than three years;
• have fewer than 25 full-time equivalent employees;
• hold gross assets of no more than £350,000 immediately before the share issue;
• carry on a new qualifying trade, be UK-established, be unquoted, and not be controlled by another company.

A company can raise up to £250,000 in total under SEIS, across all its rounds. On the investor side, SEIS gives 50% income tax relief on up to £200,000 invested per tax year, with capital gains tax exemption on the shares if they are held for at least three years. Some trades are excluded (for example financial services and property development). The fastest way to know where you stand is to run the free eligibility check, which tests your company against every condition in about five minutes.

SEIS vs EIS advance assurance

SEIS is the early round. Once a company outgrows the SEIS limits, the Enterprise Investment Scheme (EIS) takes over for larger raises. From 6 April 2026 the EIS limits expanded significantly: gross assets of up to £30 million before the share issue (£35 million after), an annual company limit of £10 million, and a lifetime limit of £24 million. EIS gives investors 30% income tax relief. Many companies raise SEIS first, up to the £250,000 cap, then move to EIS, and you can seek advance assurance for both.

How to apply for SEIS advance assurance

An advance assurance application is a structured submission to HMRC's Venture Capital Reliefs Team, together with a covering letter and supporting documents: typically your business plan, latest financials, an up-to-date structure chart, and details of the proposed raise. You can apply yourself, through an adviser, or through a platform. The two avoidable reasons applications stall are an incomplete submission and a covering letter that does not address HMRC's conditions head-on. A properly prepared application is what prevents both.

How long does SEIS advance assurance take?

HMRC's turnaround is typically four to eight weeks from a complete, correctly prepared submission, though it varies with HMRC's workload. The single biggest avoidable delay is an incomplete application, which is exactly what a properly drafted submission removes.

What does it cost?

A full advisory engagement for advance assurance typically runs to around £2,000 plus VAT. Online legal platforms charge roughly £500 plus VAT, usually on top of a subscription. Seisly prepares your complete application and drafts your covering letter for a flat £75, with no subscription, and can file with HMRC as your appointed agent for a fixed add-on. For genuinely complex structures, we refer you to a specialist adviser in our network.

Check whether you qualify, free

You can find out whether your company meets the SEIS conditions in about five minutes, with no account and no email sign-up.