How to track finances across multiple SaaS projects

Why separate products

Running several small SaaS products is a common indie path: one idea gets traction, another is a side bet, a third is winding down. If all their money lands in one bank account and one card, it is easy to know the business total and hard to know anything else. Is the new product actually costing more than it earns? Is the old one still worth the hosting bill? Those questions decide where your limited time goes, and they need per-product numbers.

A simple structure

You do not need separate companies or bank accounts per product. You need consistent labels:

1. 1.One project per product. Every income line and every direct cost belongs to exactly one.
2. 2.One shared project (call it Studio or Shared) for costs that serve several products: your laptop, accounting software, a design tool, your own salary if you pay one.
3. 3.A short, shared category list across all projects (hosting, tools, marketing, contractors, fees) so you can compare like with like.
4. 4.An account type for where money actually sits: business bank, card, processor balance. Totals per account make reconciliation quick.

The rule of thumb for direct costs: if you shut the product down tomorrow, would this cost disappear? If yes, it belongs to that product. If no, it is shared.

Shared costs

Shared costs are where people overthink it. Pick one allocation rule and stick to it so month-to-month comparisons stay fair:

• By revenue share: each product carries shared costs in proportion to its revenue. Fair to small experiments, which are not crushed by overhead.
• Evenly: each active product carries the same share. Simple, and honest about the fact that each product costs you attention.
• By time spent: closest to reality if you track time, but most founders do not, and estimates drift.

Whichever you choose, look at results before and after allocation. Before allocation (contribution) tells you whether a product covers its own direct costs. After allocation tells you whether it carries its weight in the business.

Worked example

Three products in one month, with $600 of shared costs allocated by revenue share:

Invoicer earns 80% of revenue, so it carries 80% of the $600 shared costs. The experiment earns nothing yet, so the revenue-share rule gives it no overhead, which keeps a young product from looking worse than it is. The pattern is what matters: Invoicer funds everything, Uptime bot is positive but thin, so a price increase or a cost cut there is worth a look, and the experiment costs $140 a month, which is a clear, cheap bet to keep running for a while.

Recurring costs per product

Most of a small SaaS cost base is recurring: hosting, databases, email delivery, monitoring, domains. These creep up quietly. Listing them per product, with their billing period, catches the tool you stopped using and the annual renewal that is about to land. Annual bills should be spread over twelve months when you look at monthly profit, or one product will look terrible every January.

The monthly portfolio review

Once a month, after recording everything, look at the same few numbers for each product:

• MRR and its change from last month (see how to calculate MRR).
• Contribution and profit after shared costs.
• Recurring cost total, and anything new on it.
• Overall net burn and runway (see the runway guide).

Then make one decision per product: invest, maintain, or wind down. Writing it down each month makes it obvious when a product has been on maintain for a year and should probably be sold or switched off.

Spreadsheet or tool?

A spreadsheet works for this, especially with two products and a handful of transactions. It gets harder as products and recurring costs multiply, mostly because recurring entries and summary tabs need constant upkeep. The spreadsheet comparison is honest about when a sheet is still the right choice.

SaaSMon is built around this exact structure: projects for each product, shared categories and account types, recurring rules that post themselves, budgets per project and a portfolio overview with MRR, burn and runway. The Free plan covers one project; Pro adds unlimited projects and the portfolio view for $4.99 a month.