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This page explains how subscriptions work as a concept. For step-by-step instructions on creating and managing subscriptions in the app, see Subscriptions in the Billing Workspace section.

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What is a subscription?

A subscription is the link between a customer and a plan. It is the central object in Saasybill. Every invoice, credit note, and billing event flows from a subscription. When you create a subscription, you define:
  • Who is being billed (the customer)
  • What they are being billed for (the plan)
  • How many units apply
  • When billing starts
From that point on, Saasybill manages the billing cycle automatically.

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How subscriptions drive invoices

At each renewal, Saasybill calculates the amount due based on the subscription’s current units and plan pricing, then creates an invoice directly in Xero. The revenue type on each invoice is classified automatically: This classification determines which Xero account code the invoice line item posts to.

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Subscription lifecycle

A subscription moves through a defined set of states from creation through to completion or cancellation.
An Ended subscription can be reverted back to Active if done so before it’s scheduled renewal date.

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Units

Units represent the quantity being billed: licences, users, seats, or whatever measure the plan defines. The plan sets the minimum unit floor; individual subscriptions can override this floor if needed. There are two unit values tracked on a subscription:
  • Current units: the live count, updated whenever a change is made
  • Paid units: the count that the most recent invoice was raised against
These two values may differ mid-cycle if a unit change has been made but not yet invoiced, for example, when a non-prorated update is made.

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What happens when a subscription changes

Mid-cycle changes to a subscription, such as increasing or decreasing units, trigger a billing adjustment. Whether this results in an invoice or a credit note depends on the direction of the change and your proration settings. The effective date of the change determines how the prorated amount is calculated. See Billing changes for the full logic.

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Subscription level overrides

Individual subscriptions can override certain defaults set at the company or plan level:
  • Discount: a percentage reduction that always applies to the base plan amount. When adding optional items, you can also choose to apply it to individual add-ons or charges.
  • Minimum invoice amount: the threshold below which an invoice is not approved
  • Invoice due date: the number of days after the invoice date that payment is due
  • Minimum units: overrides the plan level minimum for this specific subscription

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Optional items

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Add-ons

Add-ons are optional recurring extras that can be attached to a subscription. They are billed alongside the base plan amount at each renewal. See Add-ons for the full details.

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Charges

Charges are one-time fees that can be added to a subscription. Unlike add-ons, charges are billed once and do not recur at renewal. See Charges for the full details.