A clear starting point
Photon offers a free tier for up to ten users and Pro at $25 per month for up to 100 users. Those plans use managed shared numbers. They can be a useful way to explore an agent experience before paying for dedicated identity.
The production step
Business is listed at $250 per line per month with dedicated numbers, a group messaging API and a daily allowance of 50 new contacts. Unlimited-user wording depends on Auto Scale. A developer should request the precise scaling and billing behavior rather than extrapolate the Pro price to a large customer base.
One more architectural choice
Photon also describes Spectrum for multi-channel agents and an open-source self-hosted path. Treat the cloud plan and a Mac-based installation as separate operating models. In an evaluation, inspect participant identity in group threads and how a conversation moves between channels. The public pages do not establish our own availability or security benchmark.