@Ashish Jain Thank you for reaching out to us, Checked with my team on your ask whether "Entra ID CIAM support SAML or not" - Entra External ID for Customer tenants do not support SAML auth as if now, however we have this in our roadmap but dont have ETA on the same. However you can share your feedback here - https://feedback.azure.com/d365community/search/?q=CIAM which is closely monitored by our product team.
Let me know if you have any further questions, feel free to post back.
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