The £99/month SaaS subscription was the defining business model of the 2010s. It was predictable for vendors, simple for buyers, and generated the ARR multiples that fuelled a decade of venture investment. But buyer sophistication has caught up. Procurement teams now conduct ROI audits before renewal, and software that charges the same whether it's used 10 times or 10,000 times is increasingly unjustifiable.
Usage-Based Pricing: The New Default
Usage-based pricing (UBP) aligns cost with value delivered. AWS pioneered it in infrastructure; now it's cascading into every SaaS category. Customers pay for API calls made, documents processed, seats active, or outcomes achieved. The commercial benefit for buyers is immediate: a startup gets access to enterprise-grade tooling at startup-grade cost, and scales their bill only as their business grows.
For vendors, UBP has a counterintuitive effect on growth: it removes adoption friction at the top of the funnel (low initial commitment) while creating a natural revenue expansion motion as successful customers use more. Stripe, Twilio, and Snowflake all built multi-billion-dollar businesses on this model.
Hybrid Models: The Pragmatic Middle Ground
Pure usage-based pricing introduces revenue unpredictability for vendors and budget unpredictability for buyers. The 2026 model that most mature SaaS companies are converging on is a hybrid: a committed spend baseline (e.g., £500/month minimum) that guarantees a usage allowance, with overage charged at a per-unit rate. This gives vendors predictable base revenue and customers a safety floor — eliminating the nightmare scenario of a runaway API loop generating a £50,000 monthly bill.
Outcome-Based Pricing: The Frontier
The boldest pricing innovation is outcome-based billing — charging only when measurable business value is delivered. A legal AI tool that charges per contract reviewed and approved. A sales intelligence platform that charges per closed deal influenced. This model requires sophisticated attribution logic and customer trust, but it completely eliminates the ROI objection in procurement conversations. Early adopters of outcome-based pricing are winning enterprise deals that flat-rate competitors cannot.