The cost math everyone runs (and what it misses)
The standard comparison: an in-house senior bookkeeper or junior controller costs $85,000–$115,000 fully loaded in the US, plus software at $300–$800 a month — call it $110,000–$140,000 a year. Outsourced firms typically charge $36,000–$96,000 depending on volume and complexity.
That math misses the expensive parts: replacing the employee who leaves, training a new hire on your entity structure, paying for full-time capacity when the work justifies part-time, and having no senior backstop when the auditor calls.
Six variables to compare
- 1Volume predictability. Fluctuating transaction volumes favor outsourced providers, who absorb seasonal peaks and valleys better than fixed headcount.
- 2Niche complexity. Revenue recognition (ASC 606), multi-entity consolidations, R&D tax credits, and multi-state nexus favor a vendor who does that work across many clients.
- 3Integration depth. Tight finance-to-product connections — Stripe revenue events, usage data, custom invoicing — favor in-house people who live in the handoffs.
- 4Hiring time. Recruiting a strong controller takes 90–180 days. A vendor typically starts within 14.
- 5Scaling speed. If AP volume 5x-es next year, vendor capacity scales faster than your hiring cycle.
- 6Regulatory exposure. Healthcare, financial services, government contracting, and PII/PHI handling favor vetted firms with documented controls.
Decision table: when to outsource vs when to hire
| Situation | Outsource | Hire in-house | Why |
|---|---|---|---|
| Under $5M revenue, simple structure | Yes | No | Volume doesn't justify dedicated headcount |
| $5M–$20M, predictable volume, standard ops | Yes | Maybe | Outsourcing remains cost-effective |
| $20M–$50M, multi-entity or complex revenue | Partial | Yes, for controller | Need in-house strategic ownership |
| $50M+ or audit-heavy industry | Specialist work only | Yes, full stack | The function becomes strategic |
The hybrid path most companies should consider
Most 20–100 person companies land best on a hybrid: one in-house finance professional — a controller or finance manager — owning close, board reporting, and strategy, paired with an outsourced execution layer handling bookkeeping, accounts payable, payroll, and sales tax.
That structure gives leadership a single accountable owner, keeps institutional knowledge embedded, prices transaction processing efficiently, and survives the in-house person leaving.
The most common failure pattern we see 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.