Startup tax calculators

Free scenario tools built on 2026/27 HMRC rules. All calculators are estimation tools only: speak to a specialist before filing.

R&D Tax Relief

R&D Relief Estimator 2026/27

Estimate your R&D merged-scheme credit or ERIS payable credit on qualifying expenditure.

SEIS and EIS

SEIS and EIS Relief Calculator 2026/27

Estimate the income tax relief, CGT position and worst-case net loss for a SEIS or EIS investment in 2026/27.

Share Schemes and EMI

EMI vs Unapproved Options Calculator 2026/27

Compare the full tax take for EMI options, unapproved options and growth shares: employee income tax, CGT, NIC and the company employer NIC cost.

Founder Tax and Extraction

Founder Dividend vs Salary Calculator 2026/27

Compare the combined tax cost of salary versus dividends for a UK founder-director in 2026/27, with the Employment Allowance solo-director trap built in.