A good investor update is a monthly letter of 400 to 700 words. It takes three minutes to read and goes out on the same day every month. It needs six sections: a one-sentence headline, 3 to 5 highlights, a KPI table (actual, previous month, target), 2 or 3 challenges with the actions you're taking, 1 to 3 specific requests (your "asks"), and your runway. You don't need a €200-a-month tool or a forty-slide deck. An email does the job. What matters is consistency: an investor who gets your letter every month trusts you before you even open your next round. This guide gives you the full template, a written example you can copy, and how often to send updates at each stage.
Why a monthly letter changes your investor relationships
Most founders send news when things are going well or when they need something. You should do the opposite.
An investor who hears nothing for four months assumes the worst. In a startup, silence never reads as "everything's fine." It reads as "they have a problem they don't want to admit." A letter that lands every month, in good times and bad, builds something nothing else can: trust through consistency.
And that trust pays off. When you communicate continuously, the relationship is already warm on the day you ask for a check. The investor has followed the story, knows your numbers, and has seen how you handle tough moments. Monthly updates prepare your next funding round twelve months in advance.
There's a second, quieter benefit: the letter forces you to face your own numbers every thirty days. Some founders only discover their real runway on the day they write the cash section. Before it's a relationship tool, the letter is a way to run your company.
The 6-section template (copy it)
Here's the structure you'll find in every good investor update. You can paste it straight into an email and fill it in within thirty minutes.
1. A one-sentence headline
One sentence at the top of the email that sums up the month. "Record revenue month (+22%), but rising churn that we're tackling as a priority." The investor should understand where you stand before scrolling. If you can't sum up your month in one sentence, you don't yet know what matters.
2. 3 to 5 highlights of the month
Three to five points at most. The key facts: a customer signed, a feature shipped, a key hire, a revenue milestone reached. List eight and none of them stands out. Keep it short, one line per point.
3. The KPI table (actual, previous month, target)
This is the core of the letter. Four to six metrics in a table with three columns: this month's actual, last month, and target. Together, those three numbers tell a story a single figure can't: whether you're growing, stalling, or slipping.
4. 2 to 3 challenges + actions
Founders are tempted to skip this section. Don't. List two or three real challenges and, above all, what you're doing to fix them. Investors don't expect perfection. They want to see that you spot problems and act on them. A problem with no action attached is a complaint. With a plan, it becomes leadership.
5. The "asks": 1 to 3 specific requests
This section is what turns a letter that informs into a letter that gets you help. Your investors have networks, portfolios, and experience. Ask, and make each ask specific. Instead of "if you know anyone interesting," go for "an intro to a CFO at a Series B SaaS scale-up" or "feedback from someone who has dealt with enterprise churn on a usage-based model." Keep it to three asks at most, because beyond that your investors tune out. A specific ask gets results far more often than a vague request.
6. Runway and outlook
Two to four sentences: how many months of cash you have left, and what you're aiming for next month. Runway is simple to calculate: your cash divided by your monthly burn. Stating it plainly every month is the strongest signal of maturity you can send. It says: I know exactly where I stand.
Which KPIs to track for your model
You don't fill in the section 3 table at random. There's a core set that works for almost every startup, plus metrics that depend on your business model.
The core set for every model:
- MRR / ARR (monthly or annual recurring revenue), with its change from the previous month. The number everyone looks at first.
- Net new MRR: the breakdown of your revenue growth (new customers, expansion, contraction, churn). Two startups with the same MRR but opposite net new MRR are in very different shape.
- Net burn: what you actually burn each month, after revenue.
- Runway: your remaining months of cash. The number that tells you when you need to raise.
- Headcount: your team size, since it's often your biggest cost.
Depending on your model, add churn (the rate at which customers leave) if you're SaaS, CAC and its payback period from Series A onward, NRR (net revenue retention) if you sell B2B, or GMV if you're a marketplace. The principle: 4 to 6 numbers that genuinely drive your company, and no more.
For a detailed breakdown of which metrics to track at each stage, we have a dedicated guide: Startup KPIs: the essential metrics by stage.
How often, and how long?
The short answer: monthly, as long as you're early-stage. Consistency beats everything else.
By stage:
- Pre-seed: monthly, 300 to 500 words, informal tone, a few light metrics. At this stage, you're mostly building the habit.
- Seed: monthly, 400 to 600 words, with the KPI table. This is where you lock in the template for good.
- Series A: monthly, 500 to 700 words, full KPI table. Board meetings add to the letter without replacing it.
- Series B and beyond: monthly or quarterly. Quarterly becomes acceptable once board reporting takes over, but monthly is still preferred.
On length, stick to the three-minute rule. Investors read your letter between meetings, on their phones. If they have to download an attachment or scroll through ten screens, they'll set it aside "for later," and later never comes. Put everything in the body of the email, short and dense.
And always send it on the same day: the first Monday of the month, the 5th, the last Friday, whatever works. A fixed date turns a good intention into a ritual.
A written example of a monthly letter
Here's what it looks like in practice for a fictional seed-stage SaaS startup.
Subject: [Nimbus] May 2026 update: record month (+22% MRR), churn to watch
Hi all,
Headline: our best revenue month since launch (+22% MRR), but a rise in enterprise churn that we're tackling as a priority.
Highlights
- Signed our largest contract to date (Acme, €1,400/month).
- Shipped v2 of the export module, requested by 60% of active accounts.
- Hired our first Head of Customer Success (starting June 2).
KPIs
Metric Actual Prev. month Target MRR €18,200 €14,900 €17,000 Net new MRR +€3,300 +€1,800 +€2,100 Net burn €41,000 €38,000 €40,000 Runway 9 months 10 months n/a Churn 3.1% 1.9% <2% Challenges and actions
- Churn rose from 1.9% to 3.1%, driven by two enterprise accounts. Action: we're launching quarterly check-ins, the first goal for our new CS hire.
- The B2B sales cycle is getting longer (45 days on average). Action: we're testing a free 14-day POC for the mid-market segment.
Our asks this month
- An intro to a CFO at a Series B SaaS scale-up (a target for our enterprise offer).
- Feedback from anyone who has built a CS team from scratch.
Runway and next steps We have 9 months of cash left. Goal for June: bring churn below 2.5% and pass €20K MRR. We're aiming to open a round in the fall.
Thanks, and reply to me directly if you have any questions.
You can copy this skeleton starting this month. Swap in your numbers and keep the structure.
The most costly reporting mistakes
A few traps can wipe out the whole benefit of reporting, even when you take the time to write it.
Hiding bad news. An investor who discovers a problem you've kept from them for three months loses trust instantly, and for a long time. Being open about challenges is what makes you credible when you announce a win. Share bad news early, with your action plan alongside it.
Dressing up the numbers. Picking whichever metric flatters you each month, changing definitions from one update to the next, highlighting cumulative revenue to hide a flat MRR. An experienced investor spots these moves in ten seconds and concludes you can't be trusted on everything else. Use the same KPIs and the same definitions, every month.
Drowning the reader. A 2,000-word letter with fifteen charts doesn't look more serious. It just goes unread.
Forgetting the asks. Asking for nothing, month after month, wastes the most valuable resource on your cap table: a network that wants to help but doesn't know how. Give them a concrete way in with every letter.
FAQ
How often should you send updates to your investors?
Monthly while you're early-stage, from pre-seed through Series A. Quarterly becomes acceptable from Series B, once board reporting takes over, but monthly remains the preferred standard. Consistency matters more than the exact frequency: a short letter every month beats a detailed report every six months.
What should go in an investor update?
Six sections: a one-sentence headline, 3 to 5 highlights, a table of 4 to 6 KPIs (actual, previous month, target), 2 or 3 challenges with the actions you're taking, 1 to 3 specific requests for your investors, and your runway with the outlook for the next month. All of it in the body of an email, readable in three minutes.
Which metrics should a startup report on?
The universal core: MRR/ARR with its change, net new MRR, net burn, runway, and headcount. Depending on your model, add churn (SaaS), CAC and its payback period (from Series A), NRR (B2B), or GMV (marketplace). Aim for 4 to 6 metrics at most that genuinely drive your company.
Should you tell your investors bad news?
Yes, and early. An investor who uncovers a hidden problem loses far more trust than one who was told about a challenge you owned. Present each piece of bad news with the action plan you're putting in place to address it: that's what turns a problem into proof of leadership.
How long should an investor letter be?
400 to 700 words, readable in under three minutes, entirely in the body of the email. At pre-seed, 300 to 500 words is enough. The goal is density over completeness: every line should carry useful information.
