What Is an Investment Memo?

An investment memo is a short written case for or against investing in a company. It lays out the thesis, the evidence, the main risks, and the terms so the decision is based on reasoning instead of momentum. In plain English, it turns “I like this startup” into “here is why I would invest, what has to go right, and what could break.”

A good investment memo ends with a decision, not just a summary.

Why investors write investment memos

The point of a memo is not to sound sophisticated. The point is to force clear thinking before money goes out the door.

If you invest without writing anything down, you are usually relying on memory, emotion, and the strongest story in the room. A memo helps fix that.

• It makes you state your actual thesis in plain language.
• It separates facts from assumptions.
• It exposes what you do not know yet.
• It makes it easier to compare deals using the same lens.
• It creates a record you can revisit later to learn from outcomes.

A memo does not remove uncertainty. It makes your uncertainty visible.

What is usually in an investment memo?

There is no single correct template. The best memo is the one that forces you to confront the real questions for that specific company. Still, most useful memos cover the same core areas.

The weight of each section changes by stage and business type. A pre-seed software company, a hardware startup, and a biotech company will not be underwritten the same way. But the underlying questions are similar.

Section	Core question	What to include
Company overview	What does the company do, for whom, and why does it matter?	A one-sentence description of the company, the customer, the problem, and why this problem matters now.
Team	Why are these founders the right people to build this?	Founder-market fit, prior work, execution speed, sales ability, technical strength, resilience, and any obvious gaps.
Market	Is this a market worth winning, and can this company wedge into it?	Market structure, customer urgency, willingness to pay, distribution dynamics, and sourced market numbers if you cite them.
Product	What exists today, and what is still roadmap?	Current product, differentiation, what is technically hard, and what has to be true for the product to work.
Traction	What evidence suggests the company is actually working?	Revenue, retention, growth, usage, pipeline quality, pilots, LOIs with caveats, partnerships, or technical and manufacturing milestones.
Business model	How does this become a real business?	Pricing, margins if relevant, sales cycle, payback assumptions, and the main drivers of unit economics.
Competition	What are customers doing instead, and why can this company win?	Direct competitors, in-house alternatives, and the status quo. Explain why this team can win distribution, not just build a better product.
Risks and open questions	What could make this a bad investment?	Technical, regulatory, supply chain, go-to-market, pricing, churn, concentration, or founder risk, plus the things you still do not know.
Terms	What are you being asked to invest on?	Amount being raised, valuation or cap, discount, instrument type, and any other material economic terms.
Recommendation	Should you invest?	A clear yes or no, followed by the top reasons you are interested and the main risks you are accepting.

How to write an investment memo

1. Start with the answer. Write “I would invest” or “I would not invest,” then give one sentence explaining why.
2. Write for a skeptical reader. If a claim would not survive a basic follow-up question, it is not ready.
3. Separate facts, interpretations, and assumptions. Founder statements, diligence findings, and your own conclusions should not blur together.
4. Use the best evidence, not every piece of information. A few sharp proof points are better than a long company recap.
5. Name the real risks. Do not hide them in generic boilerplate.
6. End with the decision record. List the main reasons you are in, the main reasons you could be wrong, and what would change your mind.

For many personal investments, 1–2 pages is enough. If you cannot explain the case clearly in two pages, the problem is often the thinking, not the page limit.

A simple decision framework

If you are staring at a blank page, start by answering these five questions:

• Why this company?
• Why now?
• What is the best evidence that demand is real?
• What has to go right for this to work?
• At these terms, is the upside worth the risk?

Investment memo vs. pitch deck

People often confuse the two. They can use some of the same facts, but they do different jobs.

A pitch deck sells the company. An investment memo tests whether the pitch survives scrutiny.

Question	Pitch deck	Investment memo
Who writes it?	The company	The investor
What is it for?	To persuade	To evaluate and decide
Who is the audience?	Potential investors	You, your partners, or an investment committee
What tone does it take?	Optimistic and selective	Analytical and explicit about uncertainty
What does it emphasize?	Vision, opportunity, milestones, and upside	Thesis, evidence, risks, terms, and recommendation
How does it end?	With an ask for capital	With an invest or pass decision

When writing an investment memo makes the most sense

• When you feel unusually excited about a deal. Excitement is exactly when a memo is most useful.
• When you are comparing multiple opportunities and want a consistent way to evaluate them.
• When the terms are complicated or the price feels aggressive.
• When the company operates in an area with real technical, regulatory, or execution risk.
• When you want a decision record you can revisit later to see whether your reasoning was sound.

A great company can still be a bad investment at the wrong price.

Common mistakes in investment memos

• Writing a company description instead of an actual investment case.
• Repeating the founder’s narrative without testing it.
• Mixing hard facts, founder claims, and assumptions into one undifferentiated story.
• Talking about market size without explaining how this company gets customers.
• Treating LOIs, pilots, or partnerships as if they were the same as repeatable revenue.
• Ignoring the status quo as a competitor. “Do nothing” and “build it in-house” are often the real alternatives.
• Listing generic risks instead of naming the few that could actually make the investment fail.
• Ignoring terms because you like the team or the product.

Using Wefunder materials as research inputs

If you are evaluating a startup raising on Wefunder, the company page can be a useful starting point. Depending on the raise and what the company has shared, you may find the pitch, founder background, financial information, updates, and community Q&A.

Those materials are inputs, not conclusions. The useful move is to review them, note what is supported versus what is still uncertain, and then write your own investment case in your own words.

Frequently asked questions

What is the main purpose of an investment memo?

To make the investment case explicit. A good memo states the thesis, the evidence, the biggest risks, and the terms so you can decide deliberately.

Is an investment memo the same as a pitch deck?

No. A pitch deck is written by the company to persuade investors. An investment memo is written by the investor to decide whether the pitch holds up.

Do I need to write a memo for every investment?

No. But if you want to improve your judgment, writing at least a short memo for the deals you are most excited about pays off quickly.

How long should an investment memo be?

For a personal investment, 1–2 pages is usually enough. More complex deals can take longer, but the core case should still be easy to explain.

Should I share my investment memo?

Usually it is a private decision tool. If you do share it, be careful about confidentiality and avoid presenting assumptions or incomplete diligence as hard facts.

Bottom line

An investment memo is a forcing function. It turns “I like this” into a written thesis, names the risks, and makes the price part of the decision. The goal is not to prove you are right. The goal is to know why you acted, what you believed, and what you missed.