"Hey, while you're here, could you also take a look at the vegetable patch?"
Add-ons extend a subscription beyond the base offering. They allow customers to purchase additional value without changing their main plan, while letting businesses scale offerings cleanly. Zoho Billing offers a comprehensive, structured add-on framework that covers different types of add-ons to address real-world subscription challenges.
Standalone addons are independent enhancements that customers can attach to their existing plan whenever they prefer. They are meant to offer extra service or features that are not included in the base plan but are commonly requested.
Strategic Advantage: Standalone addons let businesses say "yes" to customer requests immediately without redesigning plans. They boost revenue, reduce complexity, and make offerings more modular. Addon Groups categorise addons into structured sections. This ensures customers see relevant options, not a long list of unrelated extras. This allows businesses to organise add-ons into meaningful groups, such as garden enhancement, soil services, and irrigation upgrades.

Recurring Addons
Recurring addons behave like mini-subscriptions attached to the main plan. They repeat every billing cycle unless removed. These are long-term additions, such as premium service layers, extra recurring hours, monthly replenishments, or ongoing feature unlocks.
Strategic Advantage: Recurring addons provide predictable recurring revenue and increase customer retention by integrating deeper value into each billing cycle. One-time Addons
These are single-use enhancements that do not renew. They are mostly occasional or emergency requests such as festival cleanup, a one-time plan installation, a deep garden care session or a special consultation.

Quantity-based Addon
Quantity-based addons allow customers to buy multiple units of a service enhancement. It depends on scaling by volume, such as purchasing more working hours, extra visits, additional fertiliser bags or extra user seats.
Strategic Advantage: This model supports incremental growth, reduces customer friction and increases recurring revenue without modifying the customer's main subscription. Usage Addons
Usage-based addons charge based on the quantity consumed, with tracking after the fact. This addon is measured purely on usage, such as irrigation water consumption, number of tasks completed, hours logged or API calls made.
Strategic Advantage: Usage based addon build trust and attract customers who prefer flexible at the same time fair way of billing. They also unlock revenue that grows organically with usage. What Addon Do for the Business
Add-ons transform how a business delivers value. Instead of forcing every customer into a rigid plan structure, they allow flexible, optional and scalable extensions that match real-world needs. This means your plan remains clean and predictable, while your revenue model becomes dynamic and adaptive.
Addons in Zoho Billing not only offer different types, but also provide flexible rules for when and how addons should be attached to a subscription. You can configure,
Association Type:
Association type controls whether the addon is optional, recommended or mandatory.
Optional: The addon can be added or removed at any time when creating or editing a subscription.
Recommended: The addons appear as a suggested enhancement on the hosted page.
Mandatory: Addon is automatically included with the plan and cannot be removed.
Applicable Event:
The applicable event defines the time range during which the addon should be considered.
Subscription activation: Triggered when a subscription goes live.
Plan Change: Triggered whenever a subscription is created or updated with a selected plan.
Trial Activation: Triggered when the trial starts.
Event Frequency
Event frequency determines whether the addon applies once or every time the event occurs.
Whenever Event Occurs: The addon is applied every time the selected event happens.
First-Time Event Occurs: The addon applies only to the first occurrence of the chosen event.
With all these addons, make your subscription model future-ready, flexible, profitable and responsive to how customers actually use your service.
Customers subscribe to your plan for the essentials. But they stay and spend more when they can tailor the service to their evolving needs.
Plans create the foundation, and addons create the experience.
