Billing¶
Understand Functional AI's billing system, subscription tiers, and usage management.
Billing Model¶
Functional AI uses a dual billing model:
- Subscription Tiers
- Monthly subscription providing message quota, storage limits, and feature access
- Pay-As-You-Go
- Optional overflow charges at $0.05/message when you exceed your tier limits
Subscription Tiers¶
| Tier | Monthly Messages | Starting Price |
|---|---|---|
| Basic | 100 | Free |
| Medium | 750 | $24.99/mo |
| Pro | 3,000 | $99.99/mo |
All users start on Basic tier (free)
No subscription purchase required to get started.
See Subscription Tiers for complete comparison.
Quick Navigation¶
| Guide | Description |
|---|---|
| Subscription Tiers | Compare tier features and limits |
| Usage Limits | Understand your quotas |
| Overflow Handling | Configure over-limit behavior |
| Managing Subscription | Upgrade, downgrade, billing |
Checking Your Usage¶
- Go to Account in the sidebar
- View usage dashboard showing current vs. limits
- Monitor days remaining in billing cycle
Key Concepts¶
Monthly Message Quota¶
- What Counts
- Each successful AI response = 1 message (regardless of length or model)
- What Doesn't Count
- User messages, failed requests, or refunded errors
- Reset Schedule
- Billing cycle date (subscriptions) or every 30 days (Basic tier)
Messages don't roll over
Unused messages reset each cycle. Each month starts fresh with your tier's full allocation.
Overflow Handling¶
When you exceed your quota, choose how to respond:
STOP Mode - Messages blocked until quota resets or you upgrade
AUTO_PAY Mode - Automatically charge $0.05/message from your account balance
How overflow charges work
Unified Rate: All tiers use $0.05 per message
Process:
- You exceed monthly quota
- System checks account balance (needs ≥ $0.05)
- Message processes if balance sufficient
- $0.05 deducted immediately
- Service stops if balance reaches $0
Balance Sources: Top-up purchases, promotional credits, or refunds
Balance Management: Never expires, visible in dashboard, refundable (minus used overflow)
See Overflow Handling for configuration.
Billing Providers¶
For: Direct website signups
Features:
- Subscription management via customer portal
- One-time top-ups ($2, $5, $10, $20)
- Prorated billing on upgrades
- Credit/debit card payments
- Separate invoices and receipts
For: Shopify app users
Features:
- Managed via Shopify admin
- Consolidated billing with Shopify account
- Usage charges for top-ups
- Follows Shopify billing policies
- Merged invoices
Both providers offer identical tier limits and features.
Common Questions¶
When does my quota reset?
With subscription: Billing cycle date | Without subscription: Every 30 days
What happens at my limit?
STOP mode: Messages blocked | AUTO_PAY mode: $0.05/message from balance
Can I upgrade mid-cycle?
Yes, takes effect immediately with prorated charges (LemonSqueezy) or per Shopify policies
Can I downgrade?
Yes, takes effect at next billing cycle
Getting Started¶
- Start on Basic tier (free)
- Configure overflow preference
- Monitor usage in dashboard
- Upgrade when needed