What is a cap table and how do I keep it clean?
By SuLe · Updated 7 July 2026
A cap table (capitalisation table) is the record of who owns what in your company: every shareholder and their shares by class, all options, and any instruments that convert into shares such as ASAs and convertible notes. You keep it clean by updating it on every change and reconciling it to your register of members and Companies House filings.
Key facts
- A cap table lists shares by class and holder, options granted and remaining, and convertibles like ASAs and notes.
- The legal record of ownership is the register of members, required under the Companies Act 2006 — the cap table must reconcile to it.
- It must also reconcile to your Companies House filings, including share allotments and the confirmation statement.
- A clean cap table shows fully diluted ownership, not just issued shares, so future dilution is visible.
- Investors run diligence on your cap table; gaps and mismatches delay or derail a round.
What exactly is a cap table?
It is a single view of ownership. At its simplest, a cap table lists each shareholder, how many shares they hold, of which class, and what percentage that represents.
A useful cap table goes further and shows the fully diluted picture: issued shares plus the whole option pool plus anything that will convert into shares later. That is the number that actually tells you how much of the company each person will end up owning.
Founders who track only issued shares flatter themselves. The option pool and outstanding convertibles are real future dilution, and a cap table that ignores them is telling you a comforting fiction.
What should a clean cap table show?
Everything that affects who owns the company, now and after everything converts. Miss a category and you will rediscover it during a fundraise, at the worst possible time.
| What to track | Why it belongs on the cap table |
|---|---|
| Ordinary shares by holder | The core of founder and shareholder ownership |
| Share classes (ordinary, preference, growth, deferred) | Different rights and different economics on an exit |
| Options granted and the remaining pool | Real future dilution, not "spare" equity |
| ASAs and convertible notes | They convert into shares at a future round |
| Vesting status | Shows how much of each holding is actually earned |
| Nominal and issue price paid | Needed for tax, buybacks and leaver pricing |
How does the cap table relate to the register of members and Companies House?
This is the distinction founders most often miss. The Companies Act 2006 requires every company to keep a register of members — that register, not your spreadsheet, is the legal record of who owns shares.
The cap table is a management tool that must reconcile to the register, and to your Companies House filings: each share allotment reported on an SH01, the shareholder and PSC information in your confirmation statement, and any transfers. If the three disagree, the statutory registers and filings win, and you have a problem to fix.
Keeping them aligned is the whole discipline. Every allotment, transfer, option exercise and conversion should update the cap table and the register together, with the matching filing made to Companies House on time.
What makes a cap table go wrong?
Drift, mostly. Equity gets promised in a meeting, shares get issued without updating the register, an option grant never makes it onto the sheet, and six months later three documents tell three different stories.
Undocumented promises are the worst offenders. "We agreed you'd get 2%" with nothing signed is both a cap table gap and a future dispute, because there is no record of the terms, the vesting, or even whether it was shares or options.
Multiple versions of the spreadsheet run a close second. When two founders each maintain their own copy, the numbers diverge quietly until someone runs diligence and finds they do not add up.
How do I keep it clean as I grow?
Give it one owner and one source of truth. Whether you use a spreadsheet or dedicated cap-table software, one person should update it the moment anything changes and reconcile it to the register and filings.
Document before you record. Every grant, transfer or conversion should have a signed document behind it — a share subscription, a stock transfer form, an option grant, a deed of adherence — before it hits the cap table.
Review it at every milestone: each hire with equity, each option grant, each new investor, and before any fundraise. A cap table you only open the week before a raise is a cap table you cannot trust.
Worked example
Sofia founds a healthtech startup, issuing herself 900,000 ordinary shares of £0.001. She later grants a lead engineer options over 50,000 shares, signs a £100,000 ASA with an angel, and reserves a 100,000-share option pool.
Her issued shares are just 900,000, but her fully diluted cap table is larger: 900,000 issued, plus 100,000 in the pool (50,000 granted, 50,000 free), plus the ASA shares that will appear when it converts. On issued shares Sofia holds 100%; fully diluted, before the ASA converts, she holds 900,000 of 1,000,000 — 90%.
She reconciles the sheet to her register of members and confirms the option grant and any allotments are documented and filed, so a future investor's diligence finds no surprises.
Where founders go wrong
Tracking only issued shares.
The option pool and outstanding convertibles are real dilution. A cap table that hides them is lying to you about your ownership.Letting the cap table and register drift apart.
The register of members is the legal record. If your spreadsheet disagrees with it, the spreadsheet is wrong.Recording undocumented promises — or forgetting documented ones.
Every entry needs a signed document behind it, and every signed grant needs to reach the sheet.Running several versions.
One owner, one source of truth. Parallel spreadsheets guarantee they eventually disagree.
Related questions
Is the cap table the same as the register of members?
No. The register of members is the legal record of who owns shares, required under the Companies Act 2006. The cap table is a management spreadsheet that also tracks options and convertibles. The cap table must reconcile to the register — if they disagree, the register is what counts in law. [More: How many shares should I issue when incorporating a UK startup?]
What should a cap table include?
Every share by class and holder, all options granted and remaining in the pool, and any instruments that convert into shares such as ASAs and convertible notes. A cap table that shows only issued shares is hiding future dilution and will surprise you at your next round. [More: How do I issue new shares in a UK company?]
Why does a messy cap table matter?
Because investors run diligence on it, and gaps kill confidence and delay closes. Unreconciled numbers, undocumented promises of equity, and missing filings all signal risk. A clean, reconciled cap table is one of the cheapest ways to look investable before a round. [More: What is due diligence — and what will investors ask for?]
How do I keep my cap table clean?
Update it the moment anything changes, reconcile it to the register of members and Companies House filings, document every grant and transfer, and track convertibles and the option pool — not just issued shares. Treat it as a live legal record, not a spreadsheet you revisit before a raise.
Who should own the cap table?
One person — usually a founder or the finance lead — with a single source of truth, whether a spreadsheet or dedicated software. Multiple conflicting versions are how errors creep in. Whoever owns it should reconcile it to the statutory registers and filings on every change.
A messy cap table is invisible until an investor's lawyer opens it — then a missing filing or an undocumented 2% promise stalls the round while you scramble to fix history. A SuLe solicitor can reconcile your cap table to your statutory registers and filings and clean up the gaps before diligence finds them. Get your founder documents reviewed — book a free consultation and go into your raise with numbers that hold up.
Keep reading: How many shares should I issue when incorporating a UK startup? · How do I issue new shares in a UK company? · What is an SH01 and when must I file it? · How do I add a new co-founder after incorporation? · What is a deed of adherence? · How big should a startup option pool be?
Primary sources: Companies Act 2006 · GOV.UK — Running a limited company
