Retell.ai vs OpenCall.ai: full comparison guide (2025)

Retell.ai

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
OpenCall.ai
$0.10/ minute
93
700 ms76%2000
Low
Retell.ai
Retell.ai
$0.07 – 0.08 /min
82
950 ms55%25
Low
Sierra AI
Sierra AI
$2 per successful outcome
79
800 ms60%30
Low
PolyAI
PolyAI
$0.25 /min (example case study)
67
1700 ms72%25
Medium
Bland AI
Bland AI
$0.09/min
66
1100 ms50%15
Low
Phonely
Phonely
$396 (yearly)
61
1200 ms52%17
Medium
Hey Rosie
Hey Rosie
$49/mo (250 min) + $0.25/min
57
950 ms60%1
Low
Smith.ai
Smith.ai
$3.25 /call (Starter 30 calls @ $97.50/mo)
55
2300 ms40%30
Medium
8x8 XCaaS
8x8 XCaaS
$60 per seat per month
49
250 ms50%15
Medium
CloudTalk
CloudTalk
$25 – $50 /user/mo
47
23 ms40%500
Low
Synthflow AI
Synthflow AI
$0.08 /min (Growth)
20
2300 ms45%20
Low
Balto.ai
Balto.ai
$100 / seat /mo
12
100 ms0%40
High