> ## Documentation Index
> Fetch the complete documentation index at: https://developer.transactbridge.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Coupons

Transact Bridge **does not provide an inbuilt coupon management system**. The merchant owns and manages the coupon system.

Merchants can use their existing coupon infrastructure while using Transact Bridge for subscription checkout and billing.

Transact Bridge supports **two ways** of applying coupons:

1. **Merchant-applied coupons** (Coupon passed during subscription creation in the API)
2. **Customer-applied coupons** (Coupon entered on the hosted checkout)

***

## Coupon Flow

```mermaid theme={null}
flowchart TB

A[Merchant Coupon System]

A --> B{Coupon Applied?}

B -->|Merchant Applies| C[Coupon Passed in<br/>Coupon Object]

B -->|Customer Applies| D[Customer Enters Coupon<br/>on Hosted Checkout]

C --> E[Checkout Opens<br/>Coupon Applied Automatically]

D --> F[TB Calls Coupon Verify API]

F --> G[Merchant Validates Coupon]

G -->|Valid| H[Discount Applied]

G -->|Invalid| I[Error Returned]

H --> J[Customer Completes Payment]
I --> D
E --> J
```

***

# Method 1: Merchant-applied Coupon

The merchant can apply a coupon while creating the subscription by passing the coupon details in the **coupon object**.

The coupon is automatically applied when the customer lands on the Transact Bridge hosted checkout page. The customer does not need to enter the coupon code manually.

For step by step integration with method 1 refer to [API ](/subscription/manage-subs/apply-coupon/api) guide.

***

# Method 2: Customer-applied Coupon

The coupon system allows partners the flexibility to use their own coupon store while enabling customers to enter coupon codes directly on the Transact Bridge hosted checkout page.

When a customer enters a coupon code, Transact Bridge calls the **Coupon Verify API** configured by the merchant.

The merchant validates the coupon in their own system and returns the appropriate response.

***

For step by step integration with method 2 refer to [checkout ](/subscription/manage-subs/apply-coupon/checkout) guide.

***

## Comparison

| Feature                     | Merchant-applied Coupon       | Customer-applied Coupon         |
| --------------------------- | ----------------------------- | ------------------------------- |
| Coupon entered by           | Merchant                      | Customer                        |
| Coupon validation           | Merchant                      | Merchant via Coupon Verify API  |
| Coupon visible on checkout  | Already applied               | Entered by customer             |
| Customer enters coupon code | No                            | Yes                             |
| API callback required       | No                            | Yes                             |
| Typical use cases           | Referral, loyalty, promotions | Public offers, campaign coupons |

***

## Notes

* Transact Bridge does not maintain or store coupons.
* Coupon creation, validation, expiry, and business rules are completely managed by the merchant.
* The Coupon Verify API is invoked only when the customer manually enters a coupon code on the hosted checkout.
* Merchants can support fixed amount discounts, percentage-based discounts, and limited-period promotional offers using their own coupon management system.