Investment memo: what it is and how to write one

TL;DR. An investment memo is the written argument for putting money into something — a company, a product bet, a build-versus-buy call. It lays out the thesis, the market, the risks, and the recommendation in prose, so a group of people can disagree with the reasoning, not just the vibe. VCs write them to make deal decisions; founders and operators write them for the same reason on any bet big enough to be wrong about expensively. The memo’s value isn’t the meeting it informs. It’s the record you read back later to find out whether you were right.

There are two kinds of expensive decision: the ones somebody wrote down first, and the ones somebody is now writing a postmortem about. An investment memo is how you stay in the first category. It’s the document an investor, founder, or operator writes to argue — on paper, with numbers — that a particular bet is worth making.

That’s the short version. The longer version is the rest of this post: what an investment memo actually is, what goes in one, why the memo beats the deck, how to write one, a miniature example, and the part every guide skips — where the memo should live after the decision is made.

What an investment memo actually is

An investment memo is a written document that makes the case for an investment: the thesis, the market, the business, the risks, and a clear recommendation, in enough detail that other people can evaluate the reasoning. It consolidates the research, structures the writer’s thinking, and gives a decision group one shared artifact to argue with instead of a slide deck and a feeling.

That’s the whole job. The format follows from it. A typical venture memo runs eight to twenty-five pages depending on stage — shorter for an early seed bet with little operating history, longer for a private-equity buyout with a decade of financials to chew through. Real published examples are worth reading; Bessemer Venture Partners publishes its actual investment memos, redacted lightly, and they’re the best primer going.

The deeper point is that an investment memo is a decision record with money attached. It belongs to the same family as a PRD, a decision record, and a team charter — durable documents a team writes to make a call and remember why. The money just raises the stakes.

What goes in an investment memo

The sections are remarkably consistent across firms. The order varies; the contents don’t. A complete investment memo structure:

Executive summary — the recommendation, the amount, the terms, and the one-paragraph thesis. Written last, read first. If a partner reads only this, they should know what you’re asking for and why.
Investment thesis — the core argument in two or three sentences. Why this, why now, why us. Everything below is evidence for this claim.
Market — size, growth, timing, and why the window is open now. The how big can this get question.
Product and traction — what the thing is, who uses it, and the evidence it’s working. Revenue, retention, growth rate, the numbers that aren’t decoration.
Business model — how it makes money, the unit economics, the path to a return.
Competition — who else is in the space and why this wins or coexists. Honest, not dismissive.
Team — why these specific people clear the bar. The most-weighted section at early stage, because the early-stage numbers barely exist.
Risks and mitigations — the reasons this fails, named plainly, with what would have to be true for it to work. The section that separates a memo from a pitch.
The ask and terms — valuation, check size, ownership, structure. The actual decision being requested.

The section that does the heavy lifting is risks. A pitch lists reasons to say yes. A memo lists the reasons to say no and then argues with them. (If your risks section says “execution risk” and stops, you have written a horoscope, not a memo.)

Why a memo beats a deck

Here’s the part the templates undersell. The reason serious firms write memos instead of just decking through a deal is that prose exposes thinking that bullet points hide.

A slide says “Large and growing market — $40B TAM.” A sentence has to say why you believe the number, where it came from, and what has to hold for it to matter. You cannot hand-wave in a full sentence the way you can in a bullet with a logo next to it. Amazon made this a company-wide rule — six-page narrative memos, no slides, read in silence at the start of the meeting — for exactly this reason: the writing forces the reasoning into the open, where it can be argued with.

Stanford’s Long-Term Investing initiative studied this directly and found that the discipline of writing a memo improves the decision itself, not just the communication of it. Writing is thinking. The memo is where you find out whether you actually believe the thesis or just like the founder. (Our CTO, Bandit, insists every forecast is “quantum” until it resolves. On investment memos, for once, he isn’t wrong — the memo is how you pin the probability down before reality collapses it.)

How to write an investment memo

The process, minus the part where you stare at a blank page for an afternoon.

Write the thesis first, in one sentence. If you can’t say why this bet wins in a sentence, you’re not ready to write the rest. Everything else is evidence for or against this line.
Gather the evidence before the prose. Pull the numbers, the market data, the references, the cohort retention. The memo is a synthesis, not a research project you do while drafting.
Write the risks section second. Before you fall in love with the deal, name every reason it fails. This is the antidote to motivated reasoning — do it while you’re still capable of saying no.
Draft in full sentences, not bullets. One claim, one paragraph, the evidence attached. If a section resists prose, the thinking underneath it isn’t done.
Put a number on the recommendation. The amount, the terms, the ownership, the expected return. A memo that ends in “seems promising” has not made a decision.
Circulate it before the meeting. The memo is read, not presented. Send it ahead; let people mark it up; spend the meeting on the disagreements, not the narration.
Keep it after the decision. Date it, version it, and store it somewhere you’ll find it in eighteen months. This is the step everyone skips, and it’s the one in the next section.

Grab our investment memo template if you want the section scaffolding without building it from scratch — and the how to write a PRD post for the closely-related skill of arguing a product bet on paper.

An investment memo example, in miniature

The show-me-one version. A real memo is pages; the shape of one fits in a paragraph.

Recommendation: Invest $2M for 12% of Acme at a $16M post-money cap. Thesis: Mid-market logistics teams still reconcile freight invoices by hand; Acme automates it, and the two design partners renewed at 3× seats. Market: ~$3B of freight-audit spend, growing as supply chains re-shore. Traction: $40K MRR, 8% month-over-month, net revenue retention 119%. Risks: single-channel acquisition; incumbent could bundle; founder has not hired a VP Sales. Mitigations: … Ask: $2M, standard seed terms, one board observer seat.

That’s the skeleton. The real memo expands each line into evidence — the cohort chart behind the retention number, the customer references behind the thesis, the model behind the market size. The discipline is identical whether the bet is a venture deal, a build-versus-buy call, or a six-figure tooling decision dressed up as a Slack thread.

The memo’s second life

Every guide tells you how to write the memo. None of them tell you what happens to it next — and that’s where most of the value leaks.

The memo’s highest use isn’t the meeting it informs. It’s the artifact you read back later. Eighteen months after the check clears, the memo is the only honest record of what you actually believed at decision time — which risks you saw, which you missed, what you predicted. Re-reading it is how a team gets calibrated: did the thesis hold, were the risks the right ones, was the team really the bet. A firm that re-reads its old memos gets better at writing new ones. A firm whose memos die in an email thread learns nothing twice.

Which means the memo has to live somewhere findable, dated, and versioned — not as a PDF attachment nobody can locate, and not in the Google Docs graveyard where decision documents go to be lost. This is the unglamorous part we built for. Raccoon Page isn’t a cap table, a data room, or a deal-flow CRM — for the deal mechanics, use the tools built for that. It’s the wiki where the reasoning lives: the memo, the PRD, the decision log, the postmortem — searchable, with full version history and one-click revert so you can see what the memo said in draft three versus what shipped. Sub-second loads, keyboard-first. The thesis you can find again is the only thesis you can learn from.

If your memos and decision records are scattered across Google Docs, the Notion import and Confluence import pull them into one searchable place in under ten minutes. The knowledge management post covers the broader discipline of keeping the durable stuff durable.

Things people actually ask

What is an investment memo? A written document that argues for a specific investment — the thesis, market, business, risks, and a clear recommendation — in enough detail that a decision group can evaluate the reasoning. It consolidates research, structures the writer’s thinking, and gives everyone one shared artifact to argue with instead of a slide deck.

What should an investment memo include? Executive summary, investment thesis, market, product and traction, business model, competition, team, risks and mitigations, and the ask with terms. The risks section is the one that separates a memo from a pitch — it names the reasons to say no and argues with them.

How long is an investment memo? Usually eight to twenty-five pages. Early-stage venture memos (seed, Series A) run shorter — eight to twelve pages — because there’s little operating history. Private-equity buyout memos can exceed thirty pages because there’s a decade of financials to analyse.

How do you write an investment memo? Write the thesis in one sentence first, gather the evidence, write the risks section before you fall for the deal, draft in full sentences rather than bullets, put a number on the recommendation, circulate it before the meeting, and keep it afterward. The full-sentences rule is the load-bearing one — prose exposes thinking that bullets hide.

Do founders write investment memos? Increasingly, yes. A founder who writes the memo a VC would write — thesis, market, risks, the honest version — both sharpens their own thinking and hands the investor a head start. Rippling’s founder famously wrote the investment memo for his own round. The skill transfers to any internal bet: a build-versus-buy call, a market-entry decision, a major hire.

What’s the difference between an investment memo and a pitch deck? A deck presents; a memo reasons. A slide can show “$40B market” with a logo and move on. A sentence has to say why you believe the number and what has to be true for it to matter. The memo is read in advance and argued with; the deck is performed live. Serious decisions lean on the memo.

Where should an investment memo be stored? Somewhere dated, versioned, and searchable — so you can read it back later and check whether the thesis held. A wiki with version history beats a PDF in an email thread or a doc in a shared-drive graveyard. The value of a memo compounds only if you can find it again.

Is an investment memo the same as an investment memorandum? Close, but not identical. An investment memo is the internal decision document covered here. A private placement memorandum (PPM) or information memorandum is a formal, legally-framed fundraising disclosure document — a different artifact with compliance requirements. People use the words loosely; the context tells you which one is meant.

An investment memo is the written argument for a bet with money attached, and the closest thing a team has to a flight recorder for its biggest decisions. Write it in full sentences, lead with the risks, end with a number — and then, the part nobody tells you, keep it somewhere you’ll actually find it again.

That last part is the one we built. Raccoon Page Free is three users, one space, a hundred pages, and no card — enough to put your memos, PRDs, and decision records in one searchable place with full version history, so eighteen months from now you can read back what you believed and find out whether the bet paid. The deck gets you through the meeting. The memo is what you have left.