Direct answer

Is building a custom system cheaper than per-seat SaaS fees over five years?

Bottom line

For most teams of ten or more, yes: typically within 12 to 24 months. The key shift is paying once for a build (usually shared across a founding cohort) plus a flat annual running fee, rather than a bill that multiplies with every new hire and rises every year. As Forbes notes: if your tool is "a simple database, a form and a dashboard," you are almost certainly overpaying rent.

Side-by-side comparison

Per-seat SaaSYour own system
Cost modelPer user, per month: compounds with headcount and annual price increasesOne-off build cost (shared across a founding cohort) + flat annual running fee
Build cost€0~€7,000 (your share of a ~€35,000 build, split across ~5 co-founders)
Annual cost: 20 users at €10/seat/mo~€2,400/yr, and rising each year~€2,500/yr flat: add unlimited users
Year 3: 30 users, 10% annual rise~€4,400/yr€2,500/yr, no change
5-year cumulative~€22,000+ (and accelerating)~€19,500 (build share + 5 × €2,500 running)
If the team doublesCost roughly doublesNo change: flat fee, unlimited users
When you stop payingAccess gone, your data is held by the vendorPerpetual, escrow-backed licence: you keep access and your data

Related questions

For teams of 10 or more using a mid-tier SaaS (€5–15/user/month), payback usually falls between 12 and 24 months after launch. For higher-cost tools like field-service or scheduling SaaS (€30–80/user/month), payback can be under a year. Use the savings calculator on the home page for your specific numbers.

Sources

  • Forbes: "Why small businesses are increasingly replacing SaaS with custom software" (2024)
  • Retool 2026 State of Internal Tools: ~35% of organisations have already replaced a SaaS with custom software; ~78% plan to replace more
  • Rollout IT build and running-cost estimates

See what your SaaS spend looks like with a flat annual fee.

Enter your seat count and current monthly price. The calculator uses real build-cost estimates and shows you the five-year crossover.