Does Phase0 use OpenAI?
Yes
We hold strong evidence for this.
- The company names it in its own subprocessor list, a statement that this vendor handles its customers' data.
How we know
About Phase0
Phase0 provides software for AVA, HOAI fees, time tracking and construction diaries. It serves small architecture and engineering offices with 1-20 employees.
Summarized from its homepage on 10 Nov 2026.
What else Phase0 uses
Phase0 has evidence for 19 vendors. The strongest:
Amazon Web Services
Amplitude
Anthropic
Attio
Customer.io
Google Cloud
Intercom
Loops
Mixpanel
Other companies using OpenAI
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