# Conversation API Release Notes

See how the Sinch Conversation API is evolving and find out about new features and bug fixes. Any notes labeled with a future date are included for preparatory reasons and are identified as such. Any breaking changes are listed under a corresponding **Breaking changes** sub-heading.

## 2026-04-01

- Improved propagation of operator identifiers in RCS message metadata
- Expanded delivery report processing to support messages sent by apps within the same project, processing the Delivery report as the original MT sender's delivery report
- Updated Smart Conversations' OCC service to use AWS resources for storage and processing


## 2026-03-31

- WhatsApp has begun propagating [business-scoped user IDs (BSUIDs)](https://developers.facebook.com/documentation/business-messaging/whatsapp/business-scoped-user-ids/#business-scoped-user-id) via webhooks. Review our [BSUID documentation](/docs/conversation/channel-support/whatsapp/user-id) to learn more and pepare your solution for this update. Specifically, if your solution parses contact identities from information provided in WhatsApp webhook events, ensure your system can process BSUIDs.
As of March 31, 2026, a contact's BSUID will be delivered as the `user_id` in the `user_profile` field of incoming WhatsApp webhook events.


## 2026-03-25

- To ensure the highest level of service reliability and to optimize communication efficiency across our ecosystem, we introduced significant updates to our incoming Conversation API traffic routing logic.
On March 25, 2026, the IP addresses associated with Conversation API base URLs changed. This was a global change affecting all regions. The base URLs themselves (for example, `https://us.conversation.api.sinch.com`) and the source IP addresses used for callbacks and webhooks remained unchanged. Only the ingress IP addresses for inbound API requests to Sinch were affected.
**If you have implemented IP whitelisting (allowlisting) rules on your network or firewalls that restrict outbound traffic to specific Sinch IP addresses, you must update them to use the new IP addresses.**
If your integration connects to Conversation API using the documented hostnames and does not restrict outbound traffic by IP address, no action is required.
If you are affected, you must update your firewall rules and/or connection configuration to include the new IP addresses.
| Environment | FQDN | Old Public IPv4 address | New Public IPv4 address |
|  --- | --- | --- | --- |
| EU1 | [eu.conversation.api.sinch.com](https://eu.conversation.api.sinch.com) | 34.246.12.7852.18.1.21752.50.172.104 | 34.247.10.25134.243.80.24163.33.21.26 |
| US1 | [us.conversation.api.sinch.com](https://us.conversation.api.sinch.com) | 44.196.133.25152.201.9.23354.243.120.247 | 52.22.60.18352.71.26.22644.221.23.197 |
| BR1 | [br.conversation.api.sinch.com](https://br.conversation.api.sinch.com) | 177.71.243.10518.228.234.25018.229.82.177 | 18.229.217.4218.230.233.8154.94.159.24 |
If you have not yet updated your configuration, we recommend doing so immediately to avoid any potential for service interruption.
- Enabled propagation of the `operator` field from the RCS `ChannelMetadata` structure for message inbound webhooks.


## 2026-03-18

- Updated `validateResponseCode` in the NRS service to properly handle error codes, with improved logging and tracing for better observability in NRS integration.


## 2026-03-11

- Updated Smart Conversations' PII service to remove support for unmarked number patterns (e.g. '123456789') from the `{NATIONAL_ID}` tag


## 2026-03-04

- Updated Smart Conversations' PII service to support currency symbols after the number (e.g. 92.50$) for the `{AMOUNT_OF_MONEY}` regex


## 2026-02-19

- Added documentation for `RCS_CARD_ORIENTATION` and `RCS_CARD_THUMBNAIL_IMAGE_ALIGNMENT` RCS channel properties


## 2026-02-11

- Improved internal error handling for MT message path
- Improved traceability for message and webhook processing


## 2026-01-14

- Enabled propagation of the `operator` field from the RCS `ChannelMetadata` structure for all positive message delivery reports


## 2025-12-17

- Improved `MESSAGE_INBOUND` callback processing by minimizing the impact of other message status updates (dedicated internal queues)


## 2025-12-10

- Added support for parsing webhook routing configurations
- Introduced a new conv-capability filter for more precise conversation searches
- Expanded filtering capabilities for Conversation and Dispatch list messages
- Improved message matching for conversations on the WhatsApp channel
- Internal performance and logging enhancements to reduce latency


## 2025-12-03

- Added new choice types: Calendar Message and Share Location Message
- Deprecated Conversation API usage of Version 1 of Template Management API
On January 31, 2026, Version 1 of the Template Management API (and the `v1` endpoint) will be fully replaced by the latest and more flexible Version 2 of the Template Management API (which uses the `v2` endpoint). Prior to that date, ensure that you have familiarized yourself with Version 2 of the Template Management API. Also ensure that any Template Management API calls in your system are updated to use the `v2` endpoint.


## 2025-11-12

- Introduced a large number of changes and improvements to the Postman collection
- Improved performance overall to prepare the system to handle increased traffic


## 2025-11-06

- Added support for custom protocols for `url_message` choices


## 2025-10-29

- Enhanced observability for fallback feature
- Added `app_id` field to synchronous capability request
- Fixed incorrect empty override for `media_message` property within `card_message` during omni template resolution


## 2025-10-15

- Increased efficiency of storing messages sent via `Dispatch Mode`


## 2025-10-08

- Improved phone-based MT matching for MOs


## 2025-09-24

- Enhanced observability for new delivery report processing
- Simplified MMS credentials validation


## 2025-09-17

- Added `channel_metadata` field for DR callbacks
- Made improvements to Postman collection corresponding to `Dispatch Mode` processing
- Added new optional OAuth2 client credentials parameters. The `client_credentials` configuration for webhook-authenticated callbacks now supports three additional optional parameters:
  - `scope`
  - `response_type`
  - `token_request_type`(`BASIC` by default, or `FORM`)


## 2025-09-03

- Internal tracing and performance improvements


## 2025-08-18

- Remove BETA annotations for Batch API
- Added **insert consent records** endpoint to [Batch API](/docs/conversation/api-reference/batch-api)
- Reworked texts in Batch API documentation


## 2025-07-01

- Internal improvements for [Delivery Receipt](/docs/conversation/callbacks/#message-delivery-receipt) race condition handling.


## 2025-06-30

- GA release of [Smart Conversations functionalities](/docs/smart-conversations/overview)


## 2025-05-28

- Callback processing improvements
- Capability check improvements


## 2025-05-14

- [Delivery Receipt](/docs/conversation/callbacks/#message-delivery-receipt) processing flow improvements.


## 2025-05-01

- Added support for [Batch Processing Report Notification](/docs/conversation/callbacks/#batch-processing-report-notification) webhook trigger.


## 2025-04-16 (breaking change)

### Breaking changes

- As of **April 16th, 2025**, a breaking change has been introduced to the Conversation API. The default [processing mode](/docs/conversation/processing-modes/) has changed from `CONVERSATION` to `DISPATCH`.
This change impacts **all new Conversation API apps**. Apps created before this date are unaffected by this change.
Please review your configurations and update any dependencies accordingly.


## 2025-04-02

- Added get batch status endpoint to [Batch API](/docs/conversation/api-reference/batch-api)


## 2025-03-26

- Added create/delete contacts endpoint to [Batch API](/docs/conversation/api-reference/batch-api)
- Replaced `POST projects/{project_id}/batches:send` with `POST projects/{project_id}/messages` in Batch API
- Replaced `POST projects/{project_id}/batches:cancel` with `DELETE projects/{project_id}/messages` in Batch API
- Deprecated `projects/{project_id}/batches` endpoint in Batch API


## 2025-03-05

- Added support for `channel_metadata` in smart conversations callbacks
- Improved handling of callbacks to avoid duplication


## 2025-02-19

- Added support credit validation on API calls. See `403` Status under [common error responses](https://developers.sinch.com/docs/conversation/api-reference/#common-error-responses).


## 2024-09-25

- Added `channel_metadata` field to callbacks. See [Callback Format](/docs/conversation/callbacks#callback-format).


## 2024-09-11

- Added support for `correlation_id` in [Dispatch processing mode](/docs/conversation/processing-modes/).


## 2024-08-21

- Added support for `conversation_metadata` in [Dispatch processing mode](/docs/conversation/processing-modes/).


## 2024-08-07

- Added forwarding of `message_metadata` in user messages with `reply_to`.


## 2024-07-24

- Infrastructure updates.
- Bug fixes and internal improvements.


## 2024-05-15

- Bug fixes and performance improvements


## 2024-05-06

- [Batch API](/docs/conversation/api-reference/batch-api) made available for open beta usage for EU and US regions
- Added partial batch handling capability with [Asynchronous Error Handling](/docs/conversation/api-reference/batch-api/#asynchronous-error-handling-in-the-conversation-api-batch-endpoint) to Batch API
- Added parameterisation support for `channel_properties`


## 2024-04-17

- [Batch API](/docs/conversation/api-reference/batch-api) made available for open beta testing for BR region
- Added partial batch handling capability with [Asynchronous Error Handling](/docs/conversation/api-reference/batch-api/#asynchronous-error-handling-in-the-conversation-api-batch-endpoint)
- Added parameterisation support for `channel_properties`


## 2024-04-03

- Added support for [Reply To](/docs/conversation/callbacks/#reply-to) to the Viber BM channel
- Bug fixes and performance improvements


## 2024-03-21

- Added support for [Flows Messages](/docs/conversation/channel-support/whatsapp/message-support/#whatsapp-flows) to the WhatsApp channel


## 2024-03-20

- Improved [Reply To](/docs/conversation/callbacks/#reply-to), increasing support time to 3 days
- Added support for [Reply To](/docs/conversation/callbacks/#reply-to) to the Telegram channel


## 2024-02-21

- Bug fixes and performance improvements


## 2024-02-14

- Fixed [update app request](/docs/conversation/api-reference/conversation/app/app_updateapp), making `display_name` field optional
- Added support for [configurable message retry time](/docs/conversation/api-reference/conversation/app/app_createapp#app/app_createapp/t=request&path=message_retry_settings) and [Delivery Report based fallback](/docs/conversation/api-reference/conversation/app/app_createapp#app/app_createapp/t=request&path=delivery_report_based_fallback)
- Bug fixes and performance improvements


## 2023-11-14

- Added `channel` field to the [list messages request](/docs/conversation/api-reference/conversation/messages/messages_listmessages#messages/messages_listmessages/t=request&in=path&path=channel) to enable filtering messages by channel
- Added `active_channel` field to the [list conversation request](/docs/conversation/api-reference/conversation/conversation/conversation_listconversations#conversation/conversation_listconversations/t=request&in=path&path=active_channel) to enable filtering conversation by its active channel
- Added new Smart Conversations powered Message Redaction Webhook Trigger. See [Redacted Messages](/docs/conversation/callbacks#redacted-messages). Note that [Smart Conversations](/docs/smart-conversations) is currently available for open beta testing.


## 2023-09-20

- Added `callback_settings` object with `secret_for_overridden_callback_urls` field to the [create app request](/docs/conversation/api-reference/conversation/app/app_createapp#app/app_createapp/t=request&path=callback_settings/secret_for_overridden_callback_urls) and [update app request](/docs/conversation/api-reference/conversation/app/app_updateapp) to enable callback verification in dynamic message delivery
- Added the `conversation_metadata_update_strategy` field to the [send message request](/docs/conversation/api-reference/conversation/messages/messages_sendmessage#messages/messages_sendmessage/t=request&path=metadata_update_strategy) (similar to the query parameter in the [conversation update request](/docs/conversation/api-reference/conversation/conversation/conversation_updateconversation))


## 2023-09-04

- Added documentation for [version 2 (V2) of the Templates API](/docs/conversation/api-reference/template/templates-v2/). Moving forward, V2 of the Templates API is the recommended version for template creation, configuration, and maintenance via API calls. Some updates include:
  - Strongly typed [`translations` field content](/docs/conversation/api-reference/template/templates-v2/templates_v2_createtemplate#templates-v2/templates_v2_createtemplate/t=request&path=translations), allowing the user to define the message using the same JSON structure used to define messages in a [send message request](/docs/conversation/api-reference/conversation/messages/messages_sendmessage#messages/messages_sendmessage/t=request&path=correlation_id)
  - Improved validation
  - The option to override the omni-channel template configuration with a channel-specific template (for channels on which channel-specific templates can be created) using the `explicit_channel_omni_message` field


## 2023-06-29

- Improved the consistency of how MO Contact deliveries (that is, when a subscriber shares a Contact record with the business) are handled. Rather than delivering the Contact as a stringified text message type, it is now delivered as a media message with a URL linking to a vCard. The vCard has a TTL of 7 days; you must retrieve the vCard from the URL within that time period.


## 2023-06-14

- Added the [`correlation_id` field to send message request](/docs/conversation/api-reference/conversation/messages/messages_sendmessage#messages/messages_sendmessage/t=request&path=correlation_id)
- Improved the handling of template messages sent with multiple channels defined. The template will now be properly evaluated for each different channel send attempt.
- Changed the `CardMessage` `title` field to optional on the send message request


## 2023-05-16

- Added format description to the documentation for the [`ttl` field of the send message request](/docs/conversation/api-reference/conversation/messages/messages_sendmessage#messages/messages_sendmessage/t=request&path=ttl) of the Conversation API


## 2023-05-10

- Stricter validation of the channels provided in the [channel priority order](/docs/conversation/api-reference/conversation/messages/messages_sendmessage#messages/messages_sendmessage/t=request&path=channel_priority_order) field of a [Send Message request](/docs/conversation/api-reference/conversation/messages/messages_sendmessage). All channels provided in this field must be configured in the corresponding Conversation API app, or the request will be rejected.


## 2023-04-19

- Added [Smart Conversations](/docs/smart-conversations) functionality to the Conversation API app configuration options available on the [Sinch Build Dashboard](https://dashboard.sinch.com/convapi/apps). This feature allows you to add artificially intelligent analysis to your Conversation API app. Note that [Smart Conversations](/docs/smart-conversations) is currently available for open beta testing.


## 2023-03-22

- Improved [list messages endpoint](/docs/conversation/api-reference/conversation/messages/messages_listmessages), with the addition of new parameters to allow filtering messages by channel identity and accept_time.


## 2023-03-08

- Extended the existing [list contacts endpoint](/docs/conversation/api-reference/conversation/contact/contact_listcontacts) to enable the retrieval of contact information based on externalId or channel-identity.


## 2023-02-01

- Improved handling of failed Send Event (POST /v1/projects/{project_id}/events:send) requests
- Deprecated Opt-In and Opt-out endpoints. They now return mocked responses to maintain backwards compatibility with existing integrations


## 2023-01-25

- Contact channel identities duplication protection mechanism in Conversation Api.


## 2023-01-11

- Updated the limit of options for choice messages to 10


## 2022-12-17

- Removed Conversation API Opt-In and Opt-Out endpoint documentation


## 2022-10-05

- Added **List** and **Get** query generators to the [Sinch Build Dashboard](https://dashboard.sinch.com/convapi/queries) to assist developers with early integration troubleshooting. These queries can be used to retrieve and display information regarding [messages](/docs/conversation/api-reference/conversation/messages), [conversations](/docs/conversation/api-reference/conversation/conversation), and [contacts](/docs/conversation/api-reference/conversation/contact).


## 2022-09-09

- Added [Markdown support](/docs/conversation/channel-support/telegram/markdown) for the Telegram Bot channel


## 2022-08-26

- Improved Conversation API metadata documentation (callbacks, conversations)


## 2022-08-10

- Queue Prioritisation to support HIGH_PRIORITY messages
- App Cache improvements
- Autoscaling improvements


## 2022-07-29

- Removed manual channel webhook configuration step when configuring Telegram and LINE channels via API


## 2022-06-01

- Added a webhook for when a contact is updated
- Added field `metadata_update_strategy` to Conversation Update


## 2022-04-27

- Added field `default_sender` to `MMSCredentials`
- Added the `injected` flag to the message object
- Added restriction to callback queue length per application


## 2022-04-13

- Improved webhook url validation


## 2022-03-21

- Internal improvements


## 2022-03-02

- Improved validation of the request body


## 2022-02-21

- Updated Postman Collection
- Moved **List Message** documentation to the **Messages** tab in the **API reference** section


## 2022-02-09

- Release of Dispatch processing mode support Beta
- Support for `SMS_MAX_NUMBER_OF_MESSAGE_PARTS` channel property on SMS channel


## 2022-01-21

- Release of WeChat channel support Beta


## 2021-12-15

- Added Processing Mode documentation
- Improved descriptions of several APIs
- Added more information to unsupported callbacks webhook
- Added support to conversation MO metadata


## 2021-11-16

- Release of LINE channel support Beta


## 2021-10-28

- Improved Apple BC card message with rich link transcoding


## 2021-09-29

- Release of Apple Business Chat channel support Beta


## 2021-09-22

- Allow 4 digit short code senders for the MMS channel
- Correctly populate the ViberBM DR timestamp


## 2021-09-21

- Improved Instagram icebreaker, shop product referral and story reply callbacks with metadata


## 2021-09-08

- Added support for Instagram private replies feature


## 2021-09-06

- Added supporting for Telegram Card & Choice Messages


## 2021-08-11

- Improved validation of Location and Choice Messages for Facebook Messenger
- Bugfix for timestamps in Viber Business contact messages
- Improved Instagram setup process with Facebook login button


## 2021-07-28

- Facebook Media Messages now support image, audio, video and document types
- Improved error messages for MMS channel media validation
- Viber Bot channel user profile query support


## 2021-07-14

- Release of KakaoTalk channel support Beta
- Improvements in validating content for WhatsApp message requests
- Validation of phone number contact identities


## 2021-07-08

- Release of Telegram channel support Beta


## 2021-06-24

- Improvements in transcoding of CardMessage and CarouselMessage for Instagram channel


## 2021-06-23

- Improvements on MMS channel for handling choice responses and contact messages that contain media attachments
- Improvements in message request validation
- Enabled setting contact metadata in message request for newly created contacts
- Handling of Suspended state for WhatsApp bots


## 2021-06-09

- Bugfixes in the CardMessage text formatting on WhatsApp and Viber Business channels
- Improvements for WhatsApp channel error response mapping and forwarding
- Support for vCard .vcf files on MMS channel in MediaMessage and CardMessage
- Support for MMS_STRICT_VALIDATION channel property to validate MMS media message contents against best practices
- Support for contact based retention policy
- New feature in Contact Management: enables fetching user profile from channels (this first release only supports Facebook Messenger)


## 2021-06-02

- Release of Instagram channel support Beta


## 2021-05-26

- Bugfix for supporting RCS CardMessage without media
- Improvements in retention policy execution


## 2021-05-12

- Improved request body validation
- Support for SMS_SENDER channel property to populate originator on SMS channel
- Added support for sending and receiving documents on Viber Business Messaging
- Improved error response mapping and forwarding on Viber Business and SMS channels
- Bugfix for keeping card order in RCS CarouselMessages


## 2021-04-28

- Improvements in Viber Business Messaging transcoding with text formatting
- Various bugfixes


## 2021-04-14

- Added support for MMS
- Added validation of URLs in MT messages
- Added validation against duplicated callback triggers
- Handle ChoiceResponseMessages on Viber Bot that have no match in the choice tracking data
- Fixed prematurely closed HTTP connection exceptions for WhatsApp
dded support for MMS
- Added validation of URLs in MT messages
- Added validation against duplicated callback triggers
- Handle ChoiceResponseMessages on Viber Bot that have no match in the choice tracking data
- Fixed prematurely closed HTTP connection exceptions for WhatsApp