THE SAAS BLOG

The accidental CFOs journey scaling a B2B SaaS

Updated: June 28th, 2025
Jonathan Rintala
Jonathan Rintala
What my accidental CFOs journey to scaling a B2B SaaS has looked like. Learning SaaS terms, running my first board meeting, and experiencing what metrics like CAC, LTV, or COGS really mean.

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What my accidental CFOs journey to scaling a B2B SaaS has looked like..

OK, so first things first. I'm no formal CFO, but I've now been building a startup for 5 years, raising venture capital, and scaling a B2B SaaS from 0 to more than 100 customers in over 10 countries.

The Startup Rollercoaster: North Star metric monthly

I'm an engineer by education, a creative by heart, a CFO by coincidence.

At the beginning of my startup journey, I was a naive first-time founder.

My first year as startup founder

Well, I guess I still am in many ways.

In the beginning, we made some rough plans in an Excel sheet and learned everything by doing.

Seeing both what worked. And what did not.

We avoided some mistakes by listening to mentors and devouring every startup book on Goodreads.

SaaS founder reading books

But tbh we still did most of the mistakes in the books ourselves. Stubborn founder style.

Along the way, I learned the SaaS language - terms like CAC, LTV, COGS, ARPA, and MRR.

Viral Growth of North Star Metric - Number of Events

But, more importantly, how these things tied to the real world.

For example, I first-handly experienced:

  • the pain of scaling a low ACV type of product outbound.

  • how difficult it was to build a PLG motion that converted with a high enough conversion rate to make an impact.

  • more recently, how our COGS will scale to diminish towards to roughly 14% over time, as they are mostly fixed costs at our current tiny scale.

Slowly but surely, we mastered parts of the CFO's predictable playbook. And started to grow reliably. But it took YEARS.

Startup founder building from Stockholm, Sweden

Now we are at a point in terms of revenue and number of customers, a point where we can finally build both:

1. meaningful projections

2. and make truly data-driven decisions.

It's alot of fun once you get there. And I realize I have a lot to learn.

What's your biggest lesson about growing a startup?