A 40-person SaaS founder asks us, “Should I hire a controller or outsource the whole stack?” The answer is almost never the one they expect, because the way the question is usually framed — cost per month, in-house versus vendor — misses four of the six variables that actually matter.
Below is how we think about it when a client asks. No spreadsheet wars, no pitch for our own services. Just the honest comparison.
The cost math everyone runs (and what it misses)
The standard cost comparison looks like this. An in-house senior bookkeeper or junior controller at $85,000 to $115,000 fully loaded in the US, plus software ($300 to $800 a month for QuickBooks Online or Xero with the add-ons), plus 10-15% in benefits and overhead. Call it $110,000 to $140,000 a year for one seat. An outsourced firm doing the same scope of work typically lands between $36,000 and $96,000 a year depending on volume and complexity.
On a pure dollar basis, outsourcing wins for most companies under $20M in revenue. What that math misses: the cost of a bookkeeper quitting in month nine, the cost of training a new hire on your specific entity structure, the cost of paying for full-time capacity when your transaction volume only justifies 12 hours a week, and the cost of not having anyone senior to ask when your auditor sends a list of questions.
Six variables to compare
The cost number is one input. The other five we ask about:
- Volume predictability. If your transaction volume swings 3x between quarters (agencies, seasonal D2C, project-based services), a firm absorbs that flex. A single in-house hire is either underused in slow months or buried in peak months.
- Niche complexity. Revenue recognition under ASC 606, multi-entity consolidations, R&D tax credits, multi-state nexus — these reward specialist depth. A firm typically has someone who has seen your specific situation; a generalist in-house hire usually has not.
- Integration depth. If your finance function needs to be wired into product (revenue events from Stripe, usage data from your app, custom invoicing logic), in-house wins. The handoffs are too tight and too frequent to vendor out.
- Hiring time. Recruiting a strong controller in a tight US market takes 90 to 180 days. A firm can start in 14. If you are 60 days from a fundraise or audit, that math is decisive.
- Scaling speed. Going from 50 to 200 employees in 18 months means your AP volume might 5x. A firm scales by adding capacity in the next sprint. In-house scales by re-running the hiring cycle every time.
- Regulatory exposure. Healthcare, financial services, government contracting, and anything dealing with PII or PHI have audit and compliance burdens that make a vetted firm with documented controls genuinely lower-risk than a solo in-house hire.
Decision table: when to outsource vs when to hire
| Your situation | Outsource | Hire in-house | Why |
|---|---|---|---|
| Under $5M revenue, simple structure | Yes | No | Volume does not justify a seat. A firm at $3-5K a month covers everything. |
| $5M-$20M, predictable volume, standard ops | Yes | Maybe | Outsourced still wins on cost. Consider a fractional CFO layer on top. |
| $20M-$50M, multi-entity or complex revenue | Partial | Yes for controller | You need someone in-house owning close. Outsource execution layers below them. |
| $50M+ or audit-heavy industry | No (except specialist work) | Yes, full stack | The function is now strategic. In-house ownership is required for control. |
The hybrid path most companies should consider
The right answer for most 20-100 person companies is not all-in on either side. It is hybrid: one in-house finance hire (controller or finance manager) owning close, board reporting, and strategic projects, sitting on top of an outsourced execution layer (bookkeeping, AP, payroll, sales tax).
That model gives you a named human accountable to your CEO, with the institutional knowledge that comes from being inside the company, and the cost efficiency of not paying full-time rates for transaction processing that does not need a full-time brain. It also gives you a backup — when your in-house person takes parental leave or quits, the firm holds the floor.
The structure we see fail most often is the opposite: a single overworked in-house bookkeeper trying to do everything alone, with no senior backstop. They burn out, they leave, and the company finds out the books have been off for three months.
Now what? If you are running this comparison yourself, the next read is our list of questions to ask any bookkeeping engagement before you sign — or look at how we structure the execution layer on our core bookkeeping service page.