Once you understand Cost Per Tenant, you can design pricing tiers that are structurally profitable rather than accidentally loss-making.
The Free Tier Trap
Freemium models are a legitimate growth strategy — but they are financially dangerous without strict cost controls. The logic is: free users cost very little individually, convert to paid at some rate, and generate word-of-mouth. This only works if the cost per free tenant is genuinely near zero.
The trap: Without enforced quotas, a free user can consume $100 of infrastructure resources. If your paid conversion rate is 5%, you need 20 free users to convert one paid user. If each of those 20 free users costs you $100 in infrastructure, you spent $2,000 to acquire one paid customer — before counting sales, marketing, or support costs.
The fix: Enforce hard resource quotas at the infrastructure level, not just the application level. "Max 500 MB storage" must be a database-enforced limit, not just a UI warning. If a free user hits the quota, they get an error — not a graceful degradation that lets them keep consuming resources.
Designing Profitable Tiers
Each tier should be designed so that the maximum possible resource consumption at that tier still yields a positive gross margin. This means:
- Model the worst case: What does a power user on the Basic plan consume? Use your 95th-percentile tenant as the design point, not the average.
- Set quotas below the break-even point: If 50 GB of storage costs $250 and your Basic plan charges $200, you cannot allow 50 GB. You must cap at ~28 GB to break even, or raise the price.
- Build overage pricing: Usage above the tier quota is billed at a per-unit rate. This converts your worst-case cost risk into revenue.
The Enterprise Pivot
For your most demanding customers — those who want unlimited usage, custom data retention, dedicated support, and security compliance — you move them from the Pool to the Silo.
- Pricing: "Enterprise — Contact Sales" (no public price, negotiated contract)
- Architecture: A dedicated single-tenant environment: their own RDS instance, their own EKS namespace or cluster, their own VPC
- Economics: You calculate the exact cost of their dedicated environment and price the contract at that cost plus a target margin (typically 60–70% gross margin for healthy SaaS). Because their costs are no longer hidden in the shared pool, there is no cross-subsidization risk
The Enterprise tier is where SaaS companies make most of their profit. The Free and Pro tiers are customer acquisition funnels. The math only works if the Enterprise contracts are large enough to subsidize the funnel — and if you know your costs well enough to price those contracts correctly.