Platform vs ready-made receptionist: who should build?
A platform is the right choice when you have engineering time and a reason to own the call flow. You get control over the model, the voice, the telephony and the data. You also get the maintenance work.
Build on a platform if:
- You have a developer who can own the integration and iterate on prompts and call logic.
- Your call flows are unusual: debt collection, multi-step verification, custom CRM writes.
- You need specific compliance controls (BAA, data residency, on-prem or VPC deployment).
- Volume is high enough that per-minute pricing beats a flat subscription.
Skip the platform route if you want a receptionist answering calls this week with no code. A ready-made AI receptionist with a flat monthly price will cost less in engineering time than the per-minute savings. Vapi's own skip-if says it plainly: small businesses wanting a ready-made receptionist with a flat monthly price and no engineering work should look elsewhere.
If you are unsure which side you fall on, our matching tool routes you based on team size and call volume.
AI voice agent platform comparison: rates, exclusions, compliance
Seven platforms, ordered by pricing transparency. Rates below are the published entry points; read the exclusions column before comparing them, because some exclude telephony and model costs.
| Platform | Published rate | What the rate excludes | Concurrency | Compliance |
|---|---|---|---|---|
| Vapi | $0.05/min hosting | Transcriber, model, voice, transport all billed on top | 4 concurrent calls free; 10 on Core ($29/mo); extra lines $10/line/mo | SOC 2, HIPAA (add-on $2,000), PCI |
| Retell AI | $0.07–$0.31/min | Range depends on voice, model, telephony choices | 20 free concurrent calls; extra $8/call/mo | HIPAA, SOC 2 Type II, GDPR, ISO 27001 |
| Bland AI | $0.14/min (Start) | Telephony billed separately; transfers $0.05/min | 10 concurrent on Start; 50 on Build ($0.12/min + $299/mo) | SOC 2 Type I & II, HIPAA, PCI DSS (self-attested), GDPR, FedRAMP 20x Class A, ISO 27001 |
| PolyAI | 2¢ per connected minute (API tier) | Telephony and orchestration not included at API rate | 10 concurrent calls included on API tier | SOC 2+ Type 2, ISO 27001, PCI DSS, GDPR |
| ElevenLabs Agents | Credit-based; plans from $0 to $990/mo | Per-minute agent rates not published; credit burn varies by product | Not published | SOC 2, HIPAA, GDPR |
| Synthflow | Quote-only; enterprise from $30,000/yr | PAYG per-call rates not stated | Custom concurrency on enterprise | SOC 2, HIPAA, PCI DSS, GDPR |
| Voiceflow | Quote-only | Usage-based billing for agencies; no stated rates | Not published | SOC 2, ISO 27001, GDPR, HIPAA |
Three of the seven publish a true per-minute entry rate. The rest require a sales conversation before you can model cost.
How do you read per-minute pricing on a voice agent platform?
The headline rate is rarely the whole bill. Three different structures exist here:
- All-in range. Retell AI publishes $0.07–$0.31/min depending on the voice, model and telephony you pick. The range is the total.
- Stack pricing. Vapi's $0.05/min is hosting only. Add Deepgram transcription ($0.0095–$0.0099/min), OpenAI intelligence ($0.0077–$0.0452/min), ElevenLabs voice ($0.0146–$0.0238/min), plus transport (Twilio inbound $0.008/min, outbound $0.014/min). The realistic total is several times the headline.
- Platform rate plus telephony. Bland's $0.14/min covers the AI stack; telephony is billed separately on your own carrier or Bland's Twilio at pass-through cost. Transfers add $0.05/min on Start.
Worked example: 300 calls at 3 minutes average (900 minutes), using our cost table:
| Platform | Monthly cost at 300 calls | Caveat |
|---|---|---|
| Retell AI | $63–$279 | Range reflects voice/model/telephony choices |
| Bland AI | $126 | Telephony extra; transfers extra |
| Vapi | $45 | Floor only: hosting. Model, voice, telephony on top |
Same call volume, a 6x spread between the lowest floor and the highest all-in figure. Always ask which components the quoted rate includes before comparing two vendors. Retell also bills during silence and hold time, because the speech-to-text engine stays active — long holds inflate minutes.
AI call center software: which vendors are enterprise-only?
Three of the seven do not publish a self-serve price you can start on today.
- Synthflow. Enterprise contracts start at $30,000 annually. That buys an enterprise SLA, native telephony or SIP trunking, custom concurrency, CRM and contact-center integrations (Cisco, Avaya, Genesys, RingCentral, Salesforce, HubSpot), a security review and launch support. A pay-as-you-go option exists when you launch a self-built agent, but the per-call rates are not stated. Final pricing depends on call volume, concurrency and telephony setup.
- PolyAI. The full Agentic Dialog Platform — telephony, integrations, testing, monitoring, 24/7 support — is quote-only. Only the model-only API tier has a published rate: 2¢ per connected minute, billed per second, with 10 concurrent calls included. New accounts get $100 in free credit for a limited time (sign-ups before 19 Nov).
- Voiceflow. No published plan prices at all. Businesses book a demo or request pricing. Agencies and partners get a free trial with no credit card and usage-based billing, but no rates or included volumes are stated. Scale indicators are strong: 3,000+ customers, 10K+ live agents, 1B+ messages processed, and a reported 70% AI resolution rate.
If you need a number before a demo, these three cannot give you one. Vapi, Retell AI and Bland can.
Picking by team type
Solo developer or small team, cost-sensitive. Vapi's free tier gives you $5 in credits, one phone number and 4 concurrent calls (Vapi pricing). Retell AI gives $10 in free credits and 20 free concurrent calls with no contract (Retell AI pricing). Both let you ship without a sales call. Watch Vapi's stacked pricing — model what a finished minute costs, not the $0.05 hosting line.
Regulated industry (healthcare, finance, insurance). Bland AI lists SOC 2 Type I & II, HIPAA, PCI DSS (self-attested), GDPR, FedRAMP 20x Class A and ISO 27001, with a BAA on Enterprise. Retell AI carries HIPAA, SOC 2 Type II, GDPR and ISO 27001 on its published-rate plan. Vapi's HIPAA handling is a $2,000 add-on, not included by default.
Multilingual operation. ElevenLabs Agents supports 90+ languages with real-time detection and switching. Bland supports 40+ languages natively with real-time translation in 23 and mid-call language switching.
High-volume enterprise with existing contact-center stack. Synthflow integrates natively with Cisco, Avaya, Genesys and RingCentral. PolyAI targets large deployments across calls, chat and messaging, with customer stories citing 42,000 missed calls turned into bookings.
CX team building across chat and voice, not just phone. Voiceflow deploys across web, app, WhatsApp, SMS and voice, with team roles, observability and white-labeling for agencies. ElevenLabs Agents also spans phone, web chat, SMS and WhatsApp.
Before you commit, run structured test calls against your shortlist. Our guide on how to test an AI receptionist applies equally to a platform-built agent.