Adding AI features to your SaaS? The flat $29/month plan that worked before breaks the moment users start hitting your LLM APIs.
Here's the honest breakdown of your three options - and what Stripe actually supports in 2026.
Read the full guide: https://osamahabib.com/blog/ai-credits-vs-usage-based-billing-saas
Why flat pricing breaks with AI
In classic SaaS, one more user costs you almost nothing. AI changes this.
Real numbers - Groq Llama 3.3 70B:
- 2,000 input tokens: ~$0.0012
- 1,000 output tokens: ~$0.0008
- Total: ~$0.002 per action
A customer running 10,000 actions/month costs you $20 in model fees alone. On a $29 plan, one heavy user kills your margin.
The 3 models compared
Usage-based - bill after use, honest, but unpredictable for customers
Prepaid credits - customer buys balance upfront, cash flow friendly,
but hides the real price
Hybrid - fixed plan with AI allowance + metered overage above it
For most early-stage SaaS, hybrid is the right default.
What Stripe actually supports in 2026
Billing Meters - basic usage-based billing, works with Checkout and Connect, but credits only reconcile at invoice time - customers can go past zero during the billing cycle
Metronome - Stripe acquired this in January 2026, handles real-time credit burndown and per-model rates, but limited Checkout/Connect support
Legacy usage records - removed in Stripe API version 2025-03-31, migrate to Billing Meters if still using old API
5-question checklist to pick your model
- One AI action or many at different costs?
- Technical buyers or non-technical teams?
- Need cash up front?
- Need hard stop at zero?
- Rely on Stripe Checkout or Connect?
Full guide with real cost maths, Stripe decision framework, and lessons from owning billing at a production SaaS:
https://osamahabib.com/blog/ai-credits-vs-usage-based-billing-saas
