# SMS REST API Release Notes See how the Sinch SMS REST API is evolving and find out about new features and bug fixes. Dates are in YYYY-MM-DD format. Note: The first instance of each notable abbreviation will be linked to the definition on our [Sinch Support Community](https://community.sinch.com/). In cases where the feature applies to many areas, we've linked to *an example of* the update. ## 2025-02-13 - Added support for [HMAC authentication configuration at the service plan level](/docs/sms/api-reference/sms/webhooks/callbacks) ## 2025-01-30 - Added support for response and scope values in OAuth 2.0 [callback validation](/docs/sms/api-reference/sms/webhooks/callbacks) ## 2024-06-13 - Added support for customized header values for [callbacks](/docs/sms/api-reference/sms/webhooks/callbacks). To configure customized headers in callbacks, reach out to your account manager. ## 2024-05-02 - Added MMS support for MO and MMS support for [receiving messages](/docs/mms/mms-mo-postbacks/) in US, Canada, Australia and Puerto Rico ## 2023-06-30 - Added MMS support (currently only supported for mobile terminated messages in the US) and MMS support for [send messages](/docs/mms/api-reference/sendmms/) ## 2023-06-20 - Limited sending to verified numbers when account is in test mode ## 2023-05-08 - Added support for `per_recipient_final` [delivery report type](/docs/sms/api-reference/sms/batches/sendsms#batches/sendsms/t=request&path=&oneof=0/delivery_report) ## 2023-03-28 - Added support for 0-prefixed shortcodes. Keyword and 0-prefixed short code based callbacks are not supported. ## 2022-05-25 - Enabled filtering on client reference when [listing delivery reports](/docs/sms/api-reference/sms/delivery-reports/getdeliveryreports) - Enabled filtering on client reference when [listing batches](/docs/sms/api-reference/sms/batches/listbatches) - Enabled filtering on client reference when [listing inbounds](/docs/sms/api-reference/sms/inbounds/listinboundmessages) ## 2022-01-21 - Stopped altering non-delivered delivery report [status codes](/docs/sms/api-reference/status-codes) from 0 to 34 ## 2022-01-02 - New encoding field in recipient delivery report visible only for messages with Auto Encoding enabled. Contact [your account manager](https://dashboard.sinch.com/account/details) to turn on Auto Encoding. ## 2021-12-07 - Added [List delivery reports](/docs/sms/api-reference/sms/delivery-reports/getdeliveryreports) endpoint ## 2021-08-31 - Allowed up to 1600 characters in [parameter values](/docs/sms/api-reference/sms/batches/sendsms#batches/sendsms/t=request&path=&oneof=0/parameters) ## 2021-06-08 - Allowed for shorter [MSISDNs](https://community.sinch.com/t5/Glossary/MSISDN/ta-p/7628) (phone numbers) to fit specific countries/places ## 2021-05-11 - [HMAC](https://community.sinch.com/t5/Glossary/HMAC/ta-p/9346) support in [callbacks](/docs/sms/api-reference/sms/webhooks/) - Added [TON](https://community.sinch.com/t5/Glossary/TON/ta-p/7760) and [NPI](https://community.sinch.com/t5/Glossary/NPI/ta-p/7646) as [optional parameters](/docs/sms/api-reference/sms/batches/sendsms#batches/sendsms/t=request&path=&oneof=0/from_ton) ## 2021-04-27 - [Date-time](/docs/sms/api-reference/sms/batches/sendsms#batches/sendsms/t=request&path=&oneof=0/send_at) format update ## 2020-10-20 - Allowed multiple access tokens per account. Contact [your account manager](https://dashboard.sinch.com/account/details) to use this feature. ## 2020-09-22 - Support for [verified numbers](https://community.sinch.com/t5/Glossary/Verified-number/ta-p/8817) - Increased max length of username for OAuth callbacks from 32 to 128 ## 2020-06-16 - Allowed sending [MCC](https://community.sinch.com/t5/Glossary/MCC/ta-p/7604)/ [MNC](https://community.sinch.com/t5/Glossary/MNC/ta-p/7615) in [delivery receipt](/docs/sms/api-reference/sms/inbounds/retrieveinboundmessage#inbounds/retrieveinboundmessage/t=response&c=200&path=&d=0/id) ## 2020-02-25 - Added [applied originator](/docs/sms/api-reference/sms/delivery-reports/getdeliveryreportbyphonenumber#delivery-reports/getdeliveryreportbyphonenumber/t=response&c=200&path=applied_originator) to delivery report ## 2019-10-12 - Increased max limit of [to](/docs/sms/api-reference/sms/batches/sendsms#batches/sendsms/t=request&path=&oneof=0/to) field from 100 to 1000. - Added ability to set max number of concat parts on account level. Contact [your account manager](https://dashboard.sinch.com/account/details) to set on account level. Or set per batch [here](/docs/sms/api-reference/sms/batches/sendsms#batches/sendsms/t=request&path=&oneof=0/max_number_of_message_parts).