# Updates the Issuing Token card reference ID for Visa to be optional

## What’s new

Updates the [network_data.visa.card_reference_id](https://docs.stripe.com/api/issuing/tokens/object.md?api-version=2026-03-25.dahlia#issuing_token_object-network_data-visa-card_reference_id) string property of the [Issuing Token](https://docs.stripe.com/api/issuing/tokens/object.md?api-version=2026-03-25.dahlia) object to be optional. Previously, it couldn’t be null.

## Why is this a breaking change?

Changes the data type of the Issuing Token object’s `network_data.visa.card_reference_id` property from string to nullable string. If your integration accesses this property and assumes that it always has a non-null value, you need to update your code to handle null values.

## Impact

The Issuing Token object now supports tokens from the Visa network that don’t have a reference ID by allowing the reference ID to be null. There is no change to the [network_data.mastercard.card_reference_id](https://docs.stripe.com/api/issuing/tokens/object.md?api-version=2026-03-25.dahlia#issuing_token_object-network_data-mastercard-card_reference_id) property, which already supports null values.

## Changes

#### REST API

| Field                                               | Change  | From → to                   |
| --------------------------------------------------- | ------- | --------------------------- |
| `Issuing.Token.network_data.visa.card_reference_id` | Changed | `string → nullable(string)` |

#### Ruby

| Field                                                  | Change  | From → to                   |
| ------------------------------------------------------ | ------- | --------------------------- |
| `Issuing::Token::NetworkDatum::Visa.card_reference_id` | Changed | `string → nullable(string)` |

#### Python

| Field                                               | Change  | From → to                   |
| --------------------------------------------------- | ------- | --------------------------- |
| `Issuing.Token.NetworkDatum.Visa.card_reference_id` | Changed | `string → nullable(string)` |

#### PHP

| Field                                               | Change  | From → to                   |
| --------------------------------------------------- | ------- | --------------------------- |
| `Issuing.Token.network_data.visa.card_reference_id` | Changed | `string → nullable(string)` |

#### Java

This change does not affect the Java SDK.

#### Node.js

| Field                                               | Change  | From → to                |
| --------------------------------------------------- | ------- | ------------------------ |
| `Issuing.Token.network_data.visa.card_reference_id` | Changed | `string → string | null` |

#### Go

This change does not affect the Go SDK.

#### .NET

This change does not affect the .NET SDK.

## Upgrade

#### REST API

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. If you use an SDK, upgrade to the corresponding SDK version for this API version.
   - If you don’t use an SDK, update your [API requests](https://docs.stripe.com/api/versioning.md) to include `Stripe-Version: 2026-03-25.dahlia`
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### Ruby

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your Ruby SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### Python

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your Python SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### PHP

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your PHP SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### Java

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your Java SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### Node.js

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your Node SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### Go

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your Go SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

#### .NET

1. [View your current API version](https://docs.stripe.com/upgrades.md#view-your-api-version-and-the-latest-available-upgrade-in-workbench) in Workbench.
1. Upgrade your .NET SDK to the latest version.
1. Upgrade the API version used for [webhook endpoints](https://docs.stripe.com/webhooks/versioning.md).
1. [Test your integration](https://docs.stripe.com/testing.md) against the new version.
1. If you use Connect, [test your Connect integration](https://docs.stripe.com/connect/testing.md).
1. In Workbench, [perform the upgrade](https://docs.stripe.com/upgrades.md#perform-the-upgrade). You can [roll back the version](https://docs.stripe.com/upgrades.md#roll-back-your-api-version) for 72 hours.

Learn more about [Stripe API upgrades](https://docs.stripe.com/upgrades.md).

## Related changes

- [Adds support for limiting the number of allowed payments for Issuing cards](https://docs.stripe.com/changelog/dahlia/2026-03-25/issuing-card-lifecycle-controls.md)