How Much Can I Invest Under SEIS? Limits Explained for 2026

The SEIS investment limits were significantly increased in April 2023 and the higher limits remain in place for 2026. This guide explains the current limits, how they apply in practice, and how investors with larger budgets can plan effectively within them.

The investor annual limit: £200,000

Each individual investor can invest up to £200,000 in SEIS-qualifying companies in a single tax year (April 6 to April 5) and claim income tax relief on the full amount. At 50%, the maximum income tax relief in a single year is £100,000.

This limit applies to your total SEIS investments across all companies in the tax year — not per company. If you invest £100,000 in Company A and £100,000 in Company B in the same tax year, you have used your full annual SEIS limit. A further SEIS investment in the same tax year would not attract income tax relief (though it might still qualify for other reliefs).

The £200,000 limit was doubled from £100,000 in April 2023 as part of the government's review of the schemes. This makes SEIS meaningfully more useful for investors who want to deploy larger amounts at seed stage.

Carry-back: using last year's limit

You can elect to treat a SEIS investment made in the current tax year as if it were made in the previous tax year — known as "carry-back." This is useful if: you have already used your current year limit, you want to offset relief against last year's higher income, or you are investing late in the tax year and want the relief available sooner.

Carry-back must be claimed on your Self Assessment return for the year you are carrying back to. You can carry back up to the unused SEIS limit in the prior year.

The company limit: £250,000

On the company side, a company can raise a maximum of £250,000 through SEIS over its lifetime. This limit also increased in 2023 from £150,000. It is a lifetime limit — not an annual limit — so a company that has raised £200,000 in SEIS can only raise a further £50,000 before needing to switch to EIS for subsequent rounds.

What if I want to invest more than £200,000 per year?

Investors wishing to invest more than £200,000 per year in early-stage companies can combine SEIS with EIS. After using the £200,000 SEIS annual limit, you can invest up to £1 million (or £2 million for knowledge-intensive companies) in EIS-qualifying companies in the same tax year. SEIS and EIS limits are separate — using one does not reduce the other.