Retell.ai vs OpenCall.ai: full comparison guide (2025)
Retell.ai
Starting at $0.07 – 0.08 /min
Retell AI offers fast, scalable voice agents with response times under a second and impressive developer flexibility. You can bring your own LLM, customize behavior deeply, and monitor everything through real-time dashboards. It’s well-suited for teams with in-house engineering that want control and scale. But the learning curve is real—getting up and running takes work, integrations often require custom scripts, and pricing isn’t transparent. While it performs well under the hood, Retell isn’t the most approachable platform for teams seeking simplicity or industry-ready templates out of the box.
Key Metrics
Latency
950 ms
Automation
55%
Integrations
25
Onboarding
1 days
Full Comparison
| Vendor | Score | Latency | Automation | Integrations | Cost | Action |
|---|---|---|---|---|---|---|
 OpenCall.ai $0.10/ minute | 93 | 700 ms | 76% | 2000 | Low | |
Retell.ai $0.07 – 0.08 /min | 82 | 950 ms | 55% | 25 | Low | |
 Sierra AI $2 per successful outcome | 79 | 800 ms | 60% | 30 | Low | |
 PolyAI $0.25 /min (example case study) | 67 | 1700 ms | 72% | 25 | Medium | |
 Bland AI $0.09/min | 66 | 1100 ms | 50% | 15 | Low | |
 Phonely $396 (yearly) | 61 | 1200 ms | 52% | 17 | Medium | |
 Hey Rosie $49/mo (250 min) + $0.25/min | 57 | 950 ms | 60% | 1 | Low | |
 Smith.ai $3.25 /call (Starter 30 calls @ $97.50/mo) | 55 | 2300 ms | 40% | 30 | Medium | |
 8x8 XCaaS $60 per seat per month | 49 | 250 ms | 50% | 15 | Medium | |
 CloudTalk $25 – $50 /user/mo | 47 | 23 ms | 40% | 500 | Low | |
 Synthflow AI $0.08 /min (Growth) | 20 | 2300 ms | 45% | 20 | Low | |
 Balto.ai $100 / seat /mo | 12 | 100 ms | 0% | 40 | High |