As part of our commitment to platform reliability, security, and scalability, Sinch is adding a brand-new, high-efficiency site to our core SMSC billing and messaging routing engine product. This site expansion introduces a next-generation, high-performance architecture to significantly increase our regional capacity, improve overall platform stability, and ensure robust message processing.
New Regional Connection Endpoints that are planned to go live 2026-10-01 during the target window:
US SMPP: us6.smpp.api.sinch.com: US HTTP SMS: us6.httpsms.api.sinch.com US Lookup API: us6.httplookup.api.sinch.com
Type: Service Announcement & Maintenance Maintenance start time: 2026-10-01 07:00 UTC Maintenance end time: 2026-10-01 08:00 UTC
Action Required: Firewall Whitelisting
To ensure uninterrupted message delivery as we scale our traffic to include this new site we request that you update your firewall settings.
Affected API Endpoint: (This change only affects customers connecting to either of the following US endpoints)
US SMPP: us1.smpp.api.sinch.com and/or us7.smpp.api.sinch.com US HTTP SMS: us1.httpsms.api.sinch.com and/or us7.httpsms.api.sinch.com US Lookup API: us1.httplookup.api.sinch.com and/or us7.httplookup.api.sinch.com
IP Addresses to Whitelist Please coordinate with your network security team to whitelist these target IP addresses:
35.95.194.74 44.239.11.143 52.32.122.205
If for any reason the maintenance is extended, cancelled, or postponed, we will advise you accordingly.
Please contact support@sinch.com should you require further information or assistance.
Posted Jul 10, 2026 - 08:37 UTC
This scheduled maintenance affects: Messaging APIs (SMPP - US, HTTP - US) and Lookup API Endpoints (ENUM US, HTTP US).