Equity Calculators Compared: What the Top Sites Offer
Updated October 2026 · 2026/27 UK tax year
We reviewed the calculators and guides that currently show up for searches like “share incentive plan calculator” to understand what users are offered and where there are gaps. The observations below come from reading the public pages in October 2026. Features change, so check each site directly.
What we found
| Site | Type | What it does well | Limits we noticed |
|---|---|---|---|
| UK Calculator (ukcalculator.com) | UK-specific calculator pages | Separate pages for SIP, profit sharing and share schemes; tables of SIP limits; FAQs; links to GOV.UK sources | Calculators are simple annual benefit estimates; no multi-year growth projection or vesting timetable |
| TotalCalcHub (Canada page) | Country-specific calculator | Clear tax treatment tables and step-by-step action plan for Canadian employees | Aimed at Canada, not the UK SIP; explicitly says UK rules differ |
| J.P. Morgan Workplace Solutions | Provider guide | Explains the four types of SIP shares, employer and employee benefits, and risks | An explanatory guide, with no calculator on the page we reviewed |
| RSM UK | Adviser PDF | Detailed tax-treatment table for withdrawals and employer benefits | Static document aimed at employers; no calculator |
| GOV.UK and HMRC manuals | Official guidance | The authoritative source for rules, limits and reporting | Written for compliance, not for estimating personal outcomes |
Gaps we set out to fill
- Multi-year projection: most tools show a single year. Our UK SIP calculator compounds contributions and applies the holding-period rules.
- Cash-versus-shares comparison: we show what the same take-home pay would be worth if invested outside the plan.
- Several schemes in one place: SIP, EMI, vesting and ESPP tools share consistent assumptions.
- Visible methodology: each page lists the rates and limits it uses, and our methodology page links to the official sources.
What to look for in any equity calculator
- Which tax year and which rates it uses, and whether they are shown on the page.
- Whether it applies the holding-period and annual-limit rules rather than a flat tax rate.
- Whether it states what it ignores (for example the personal allowance taper, Scottish rates or state taxes).
- Links to official sources so you can verify the numbers.
Frequently asked questions
Which SIP calculator is the most accurate?
Accuracy depends on how current the rates are and how many rules are modelled. Check the tax year shown, whether limits are applied, and whether the tool links to GOV.UK or HMRC guidance. None replaces advice from a qualified adviser.
Written and maintained by the EquityCalc Hub editorial team. Tax figures reviewed for the 2026/27 UK tax year. Last updated October 2026. See our methodology and sources. This page is general information, not tax or financial advice.