Source note · Calls-per-second limits on SIP trunks and dialers
Twilio returns '503 Trunk concurrent call limit exceeded' when a trial account or one without an approved Business Profile exceeds 4 simultaneous termination calls.
Checked 2026-10-02
- Vendor
- Twilio
- Product
- Elastic SIP Trunking
- Subsystem
- concurrent calls
- Deployment
- multi-tenant
- Region
- not restricted
- Release range
- current as of 2026-10-02
- Checked
- 2026-10-02
Sources
- Troubleshooting your Trunk — Twilio · tier 2 current vendor documentation · Termination calls: 'The call fails with a 503 Trunk concurrent call limit exceeded error'
Cite this note
APA
WarmTransfer. (2026, October 2). Calls-per-second limits on SIP trunks and dialers: source note sip-trunk-cps-limits-twilio-503-concurrent. WarmTransfer. https://warmtransfer.net/knowledge/claims/sip-trunk-cps-limits-twilio-503-concurrent
BibTeX
@misc{warmtransfer-claim-sip-trunk-cps-limits-twilio-503-concurrent,
title = {Calls-per-second limits on SIP trunks and dialers: source note sip-trunk-cps-limits-twilio-503-concurrent},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/sip-trunk-cps-limits-twilio-503-concurrent},
note = {Source note sip-trunk-cps-limits-twilio-503-concurrent, checked 2026-10-02}
}