Billing

How billing works with Usage Based meters in Solifyn

Metered Pricing Model

Solifyn charges customers based on unit consumption tracked by your configured meters.

Unit Pricing with Free Threshold

Solifyn uses a simple unit pricing model with an optional Free Threshold. For each meter associated with a product or subscription plan, you define:

• Price per unit: The cost charged for each individual unit of usage.
• Free threshold: The number of units that are included for free in the billing cycle before charges start accumulating.

Cost Calculation Formula

During billing aggregation, Solifyn calculates the total billable cost as follows:

$\text{Billable Usage} = \max(0, \text{Total Usage} - \text{Free Threshold})$ $\text{Total Cost} = \text{Billable Usage} \times \text{Price Per Unit}$

Example:

If you set:

• Meter: api.requests
• Price per unit: $0.01
• Free threshold: 1,000

Customer Usage	Billable Usage	Calculated Cost
850 requests	0 requests	$0.00
1,500 requests	500 requests	$5.00

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Associating Meters with Products and Plans

To enable metered billing:

1. Navigate to the product creation/edit form.
2. Select your desired usage meter.
3. Input the Price per unit and Free Threshold.
4. Save the product configuration.

Behind the scenes, this links the meter to the product/plan via ProductMeter or PlanMeter associations.

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Invoicing & Billing Cycle

• Subscription renewal: Accumulated usage is computed over the billing period and added as a line item on the invoice at the end of the billing cycle.
• Subscription cancellation: If a subscription is canceled, it remains active through the end of the billing cycle (grace period). Accumulated usage charges continue to be tracked and are billed in a final invoice when the cycle expires.