Three months ago, a client asked me to spec out an AI voice agent for their dental practice. They wanted to automate appointment confirmations, handle after-hours calls, and route emergencies. Simple enough, right?
I pulled up four vendor pricing pages. Each one quoted a per-minute rate that looked reasonable. Then I started doing the actual math -- telephony costs, LLM token costs, voice synthesis costs, phone number fees, platform fees, overage charges. The "$0.07 per minute" headline price turned into $0.18 per minute fully loaded.
That experience made me angry enough to write this post. AI voice agent pricing is deliberately confusing. Every vendor advertises a low per-minute rate and buries the rest. I'm going to lay out what things actually cost so you can budget properly before signing anything.
The Anatomy of a Voice Agent Bill
Before we compare vendors, you need to understand the five cost layers. Every single AI voice agent involves all five, whether the vendor bundles them or bills them separately.
1. Voice synthesis (text-to-speech). This is the AI generating speech from text. Costs vary based on voice quality -- the more natural-sounding, the more expensive. Basic voices run $0.01-0.02/minute. Premium cloned voices hit $0.04-0.08/minute.
2. Speech recognition (speech-to-text). Converting caller speech into text for the LLM to process. Usually $0.006-0.01/minute. Deepgram and AssemblyAI are the main providers here.
3. LLM processing. The AI brain -- GPT-4o, Claude, or similar -- figuring out what to say. This is token-based. A typical 3-minute call uses 1,500-3,000 tokens. At GPT-4o mini rates ($0.15/$0.60 per million tokens), that's about $0.001 per call. At GPT-4o rates ($2.50/$10 per million), it's $0.01-0.03 per call. Small individually, adds up at volume.
4. Telephony. Actual phone call costs. Inbound and outbound rates vary by country. US calls: $0.01-0.03/minute. Plus phone number rental: $1-3/month per number. Some vendors include this, many don't.
5. Platform fee. The vendor's software, infrastructure, and margin. This is either baked into the per-minute rate or charged as a monthly subscription. Sometimes both.
Vendor-by-Vendor Pricing Breakdown
Bland.ai
Bland is the most straightforward pricing in the space, which is why we use them for a lot of client work. Their model: you pay per minute, and most costs are bundled.
- Standard: $0.07/minute connected time. Includes basic TTS, STT, and telephony.
- Pro voices: $0.09-0.12/minute. Better voice quality, lower latency.
- Enterprise: Volume discounts starting at 10,000 minutes/month. We've negotiated $0.05/minute for large accounts.
- LLM costs: Included for their default model. GPT-4o or Claude add $0.01-0.03/minute on top.
- Phone numbers: $2/month per number.
What they don't tell you: The $0.07/minute rate uses their built-in model, which is fine for simple scripts but noticeably worse than GPT-4o for complex conversations. The moment you switch to a premium LLM, you're at $0.10-0.15/minute. Also, you only pay for connected time (good), but the minimum charge per call is 6 seconds.
Real-world cost: For a dental practice running appointment confirmations with GPT-4o and pro voices -- $0.12/minute average. A 2-minute call costs about $0.24.
Synthflow
Synthflow targets non-technical users with a visual builder. Their pricing is subscription-based with minute bundles.
- Starter: $29/month for 50 minutes. That's $0.58/minute if you do the math. Yikes.
- Pro: $450/month for 2,000 minutes ($0.225/minute). More reasonable.
- Growth: $900/month for 4,000 minutes ($0.225/minute).
- Agency: $1,400/month for 6,000 minutes ($0.233/minute).
- Overages: $0.08-0.15/minute depending on plan.
What they don't tell you: The subscription includes their platform and basic voices, but premium ElevenLabs voices (which sound dramatically better) cost extra. Also, their minutes are "talk time" -- the time the AI is actually speaking, not total call duration. A 3-minute call might use 1.5-2 minutes of talk time, which is better than it sounds but still confusing.
Synthflow does shine for agencies reselling voice AI to clients. Their white-label features and visual builder make it easy to set up campaigns without developers. But you're paying a premium for that convenience.
Real-world cost: On the Pro plan with ElevenLabs voices and actual usage patterns, we measured $0.28-0.35 per minute of total call duration. A 2-minute call costs about $0.56-0.70.
Vapi
Vapi is the developer-first platform. Think of it as the "build your own" option with maximum control. Their pricing reflects this -- it's modular and transparent, but you need to add up all the pieces.
- Platform fee: $0.05/minute. This is just Vapi's infrastructure.
- Voice (TTS): Bring your own. ElevenLabs ~$0.04-0.08/min, PlayHT ~$0.03-0.05/min, Deepgram ~$0.02/min.
- Transcription (STT): Deepgram $0.006/min, AssemblyAI $0.01/min.
- LLM: Bring your own API key. GPT-4o mini ~$0.001/min, GPT-4o ~$0.02/min, Claude 3.5 Sonnet ~$0.015/min.
- Telephony: Twilio integration. ~$0.013/min US calls + $1/month per number.
What they don't tell you: Nothing, honestly. Vapi is the most transparent pricing in the space. The catch is that you need developer skills to set it up, and you're managing multiple vendor relationships (Vapi + voice provider + LLM provider + telephony provider). If anything breaks, you're debugging across four systems.
Real-world cost: Vapi + ElevenLabs Turbo v2 + GPT-4o mini + Deepgram + Twilio = approximately $0.12-0.14/minute. A 2-minute call costs about $0.24-0.28. With GPT-4o instead of mini: $0.15-0.18/minute.
ElevenLabs Conversational AI
ElevenLabs entered the voice agent space in late 2025. They're primarily a voice synthesis company, so the voice quality is best-in-class. But their agent platform is newer and less battle-tested.
- Free: 15 minutes/month. Testing only.
- Starter: $5/month + ~$0.08/minute for conversational AI.
- Scale: $22/month + ~$0.05/minute.
- Business: $99/month + ~$0.04/minute.
- Enterprise: Custom, with volume discounts.
What they don't tell you: These rates cover voice synthesis only. Telephony is extra (they use Twilio under the hood). LLM costs are separate. And their agent platform, while improving rapidly, doesn't have the workflow complexity of Bland.ai or Vapi yet. Limited branching logic, basic tool calling.
The voice quality, though -- it's unmatched. If your use case demands the most natural-sounding voice (luxury brands, healthcare where empathy matters, high-touch sales), ElevenLabs is where you start. For a full comparison, see our ElevenLabs vs Synthflow breakdown.
Real-world cost: ElevenLabs Scale + GPT-4o + Twilio telephony = approximately $0.14-0.20/minute. Premium voices push this to $0.20-0.28/minute. A 2-minute call: $0.28-0.56 depending on voice tier.
Total Cost Examples: 100, 1,000, and 10,000 Calls/Month
Enough theory. Here's what you'd actually pay, assuming an average call duration of 2.5 minutes and a standard GPT-4o mini stack.
100 Calls Per Month (Small Business)
Total minutes: ~250/month. This is a small dental office, a solo real estate agent, or a local service business handling after-hours calls.
- Bland.ai: ~$30/month (250 min x $0.12) + $2 phone number = $32/month
- Synthflow: $29/month Starter (50 min included) + overage for 200 min = ~$53/month
- Vapi: ~$33/month (250 min x $0.13) + $1 phone number = $34/month
- ElevenLabs: $22/month Scale + ~$18 (250 min x ~$0.07 for remaining stack) = ~$40/month
At this volume, the differences are small. You're looking at $32-53/month. Bland.ai and Vapi are cheapest. Synthflow's Starter plan is overpriced for the minutes included. Compare that to a part-time receptionist at $15-20/hour -- even 2 hours per week is $130-160/month. The AI voice agent pays for itself in the first week.
1,000 Calls Per Month (Growing Business)
Total minutes: ~2,500/month. A mid-size medical practice, a regional insurance agency, or an e-commerce company handling order status calls.
- Bland.ai: ~$300/month (2,500 min x $0.12) + $2 phone number = $302/month
- Synthflow: $450/month Pro (2,000 min) + $40 overage (500 min x $0.08) = $490/month
- Vapi: ~$325/month (2,500 min x $0.13) + $1 phone number = $326/month
- ElevenLabs: $99/month Business + ~$175 (2,500 min x ~$0.07 remaining stack) = ~$274/month
Now the spread matters. ElevenLabs' Business plan starts saving money at volume. Synthflow is the most expensive by a wide margin. Bland.ai and Vapi are in the middle. At 1,000 calls/month, you're replacing 1-2 full-time phone staff ($3,500-7,000/month). Even the most expensive option here is 93% cheaper than human agents.
10,000 Calls Per Month (Enterprise/Call Center)
Total minutes: ~25,000/month. A regional call center, a national service company, or a large healthcare system.
- Bland.ai (Enterprise): ~$1,500/month (25,000 min x $0.06 negotiated) + phone numbers = ~$1,520/month
- Synthflow (Agency): $1,400/month (6,000 min) + $1,520 overage (19,000 min x $0.08) = ~$2,920/month
- Vapi: ~$2,750/month (25,000 min x $0.11 with volume optimization) = ~$2,750/month
- ElevenLabs (Enterprise): Custom pricing, typically ~$1,800-2,200/month at this volume.
At enterprise volume, Bland.ai's negotiated rates win. Synthflow's bundled pricing model falls apart completely at scale -- you're paying $2,920/month when Bland.ai does the same for $1,520. Vapi stays competitive but the modular cost structure means you're optimizing across four vendors to keep costs down.
The Hidden Costs Nobody Mentions
The per-minute rates are just the beginning. Here's what catches people off guard:
Setup and configuration: $500-5,000. Building a production-quality voice agent takes 20-80 hours depending on complexity. Prompt engineering, conversation flow design, edge case handling, testing. You're either paying a developer or an agency (like ours) to do this right.
Voice cloning: $0-500. If you want a custom voice that matches your brand, most platforms charge for voice cloning. ElevenLabs charges based on plan tier (free on Scale+). Bland.ai charges a one-time fee. Budget $200-500 for a professional-quality custom voice.
Phone numbers: $1-15/month each. Standard US numbers run $1-3/month. Toll-free: $3-5/month. Local numbers in multiple area codes: $1-2 each. A business with 5 local numbers is paying $5-10/month just for phone lines.
Twilio/telephony markup: 10-40%. Platforms that use Twilio under the hood mark up the telephony costs. Vapi is transparent about this. Others bake it into their rate. If a vendor won't tell you their telephony provider, assume a 30% markup.
LLM cost spikes. Complex conversations use more tokens. A 5-minute call where the customer asks 8 questions and the AI needs to look up data can use 5,000+ tokens. At GPT-4o rates, that's $0.05 in LLM costs alone. Multiply by 10,000 calls and you've got $500/month in LLM costs that weren't in the vendor quote.
Monitoring and maintenance: $200-500/month. Someone needs to review call logs, update prompts, handle edge cases, and fix issues. This is ongoing. The agent doesn't maintain itself. We charge clients $300/month for basic monitoring and prompt optimization. Doing it in-house takes 5-10 hours/month of someone's time.
How to Cut Costs by 30-50%
We've optimized voice agent costs for dozens of deployments. Here's what actually moves the needle:
Use GPT-4o mini for 80% of calls. Most inbound calls are routine -- appointment confirmations, business hours, order status. GPT-4o mini handles these perfectly at 95% lower LLM cost. Route complex calls to GPT-4o or transfer to a human. This alone cuts LLM costs by 70-80%.
Optimize conversation length. A well-designed conversation flow completes the same task in 1.5 minutes instead of 3. That's 50% savings on every per-minute cost. Get to the point. Confirm quickly. Don't let the AI ramble.
Negotiate annual commitments. Every vendor offers 15-30% discounts for annual contracts. At 1,000+ calls/month, this is worth negotiating. We've gotten 40% discounts for clients committing to 12-month terms with volume minimums.
Use webhooks instead of polling. Some platforms charge for "keep-alive" time while waiting for webhook responses. Structure your integrations to minimize wait states. Every second the call is open costs money.
Batch similar calls. If you're making outbound calls (appointment reminders, follow-ups), batch them during off-peak hours. Some telephony providers offer lower rates for off-peak. It's a small savings per call but adds up at 10,000+ calls/month.
Build vs. Buy: The Real Decision
You have two paths:
Use a platform (Bland.ai, Synthflow, ElevenLabs): Faster to deploy (days, not weeks). Higher per-minute costs. Less customization. Best for businesses under 5,000 calls/month.
Build on Vapi or raw APIs: More setup time (weeks to months). Lower per-minute costs at scale. Full customization. Best for businesses over 5,000 calls/month or with unique requirements.
The break-even point where building your own becomes cheaper than a platform is typically around 3,000-5,000 calls per month. Below that, the development and maintenance costs don't justify the per-minute savings.
There's a third path: hire an agency to build and manage it. That's what most of our AI voice agent clients do. We handle the architecture, integration, and ongoing optimization. They get enterprise-grade voice AI without the technical overhead. Setup runs $2,000-8,000 depending on complexity, plus $300-800/month for management.
The Bottom Line
AI voice agents in 2026 cost between $0.12-0.35 per minute fully loaded, depending on voice quality, LLM choice, and platform. For a small business taking 100 calls/month, budget $30-55/month. For a mid-size company at 1,000 calls/month, budget $275-490/month. For enterprise at 10,000 calls/month, budget $1,500-2,900/month.
These numbers are 85-95% cheaper than human agents for equivalent call volumes. The ROI is almost always positive within the first month. The question isn't whether to deploy voice AI -- it's which vendor and architecture give you the best cost-to-quality ratio for your specific use case.
If you want us to run the numbers for your business, reach out. We'll model the total cost across platforms and tell you exactly what to expect. No sales pitch -- just math.
