The Vapi Alternative With
Predictable All-Inclusive Pricing
Phone Stack is a complete AI voice agent platform and a Vapi alternative for teams that want one predictable bill. Vapi charges a $0.05/minute orchestration base with STT, TTS, LLM, and telephony stacked on top ($0.07–$0.25/minute all-in), plus a $1,000/month HIPAA add-on. Phone Stack bundles everything into one rate from $0.18/minute, with HIPAA BAAs included on Enterprise and 30 free minutes to start.
No credit card required.
Vapi pricing vs Phone Stack pricing
Vapi's headline number is a $0.05/minute orchestration base — but that's the platform fee, not the price of a call. Speech-to-text, text-to-speech, LLM tokens, and telephony each bill on top, so the true all-in cost lands anywhere from $0.07 to $0.25 per minute depending on the models you pick. Phone Stack charges one all-inclusive rate that covers the entire pipeline: voice AI, telephony, transcription, post-call analysis, CRM sync, and compliance tooling.
Pricing verified 2026-06.
| Pricing | Vapi | Phone Stack |
|---|---|---|
| Headline rate | $0.05/min (orchestration only) | From $0.18/min (everything included) |
| True all-in per minute | $0.07–$0.25/min depending on STT, TTS, and LLM choices | $0.18/min on Enterprise; $0.20–$0.25/min on self-serve credit packs |
| HIPAA | $1,000/mo add-on | Included on Enterprise (signed BAA, no add-on fee) |
| Enterprise | $40K–$70K/year | $1,800/mo with 10,000 minutes included ($21.6K/year) |
Worked example: 3,000 minutes per month
Vapi
- Orchestration base: 3,000 min × $0.05 = $150 — before any STT, TTS, LLM, or telephony costs
- True all-in: 3,000 min × $0.07–$0.25 = $210–$750/mo depending on model choices
- Your bill moves whenever you change models — or when a provider changes theirs
Phone Stack
- 3,000 min × $0.18 = $540/mo at the Enterprise rate ($1,800/mo plan with 10,000 minutes included)
- On the self-serve Scale credit pack it's 3,000 min × $0.20 = $600 — still one number, nothing stacked on top
- The rate is the bill. No component line items.
To be fair: if you stay at the very bottom of Vapi's model range, Vapi can come in cheaper at this volume. The trade is predictability — Phone Stack's number doesn't move when you want better voices or a stronger model, and there's no engineering time spent assembling and maintaining the stack.
The HIPAA scenario
If your calls touch protected health information, Vapi's $1,000/month HIPAA add-on changes the math. At 3,000 minutes/month, Vapi runs $210–$750 in usage plus $1,000 for HIPAA = $1,210–$1,750/mo. At Enterprise volume — 10,000 minutes/month — Vapi's usage is $700–$2,500 plus the $1,000 add-on = $1,700–$3,500/mo. Phone Stack's Enterprise plan is a flat $1,800/mo with 10,000 minutes and the signed BAA included. At lower volumes the two can be comparable; as volume grows toward Enterprise scale, the flat rate wins across nearly all of Vapi's model range — and it never surprises you.
Full tier details are on our pricing page: the $0.18/min rate is specific to the Enterprise plan, while self-serve credit packs run $0.20–$0.25/min with no monthly commitment.
Phone Stack vs Vapi: feature by feature
Vapi gives you voice infrastructure to build on. Phone Stack gives you a finished operation — campaign engine, supervision, and compliance included. (Claims verified 2026-06.)
| Feature | Phone Stack | Vapi |
|---|---|---|
| Pricing model | All-inclusive from $0.18/min | Usage-based (STT + TTS + LLM separate) |
| Voice latency | ~320ms (native S2S) | ~400–700ms |
| Setup | Zero-code, chat training | API / developer required |
| Inbound calls | ||
| Outbound calls | ||
| Campaign engine | ||
| Listen Live | ||
| Barge In | ||
| HIPAA ready | ||
| TCPA compliance | ||
| CRM integrations | Native (HubSpot, GCal, 40+) | Via API |
| Voicemail detection | ||
| Free trial | 30 min free | Free tier |
Everything Vapi leaves as an exercise for your team
Vapi is honest about what it is: middleware. It orchestrates the voice pipeline and leaves the application layer to you. That means building your own outbound dialer and queueing, voicemail handling, supervisor tooling, CRM writeback, and compliance workflows — then maintaining them.
- Built-in campaign engine with contact-list dispatch, voicemail detection, and post-call actions — the core of our AI-powered call center platform
- Listen Live and Barge In, so supervisors can monitor any call and take over instantly
- TCPA tooling: consent tracking, calling-window enforcement, recording disclosures, and DNC management
- ~320ms native speech-to-speech — no STT→LLM→TTS chain to tune. Every outbound voice agent ships with it by default
- Native CRM integrations (HubSpot, Google Calendar, 40+ tools) plus a REST API and webhooks when you do want code
Comparing more than one platform? See how Phone Stack stacks up against Retell, Bland, and Synthflow on the full comparison page.
When Vapi is the better choice
Vapi is a genuinely strong developer platform, and for some teams it's the right call. It has become the benchmark competitors measure themselves against for a reason. Pick Vapi over Phone Stack when:
- You're a developer building a fully custom voice stack and want maximum model flexibility
- You want to optimize every pipeline component yourself and can manage variable per-minute costs
If model-level control is your core requirement — swapping STT providers, A/B-testing TTS voices from different vendors, routing different calls to different LLMs — Vapi's flexible middleware approach is exactly what you want, and its $0.05/min orchestration base keeps the platform layer cheap. Phone Stack makes those choices for you in exchange for one rate, ~320ms latency, and a launch measured in minutes.
How to migrate from Vapi to Phone Stack
There's no pipeline to rebuild — only the agent's knowledge to carry over. Most teams complete the move within a day.
- 1
Export your Vapi assistant configs and prompts
Pull your assistant definitions, system prompts, and call flows from the Vapi dashboard or API. These are the source material for retraining — you won't need the pipeline code.
- 2
Recreate your agent via chat training
Phone Stack has no assistant API to configure. Paste your prompts and describe your call goals in the chat trainer — it works like onboarding an employee. Most agents are retrained in 15–30 minutes.
- 3
Port or provision phone numbers
Port your existing numbers or buy new ones inside Phone Stack. Inbound routing and outbound caller ID are configured from the dashboard, not via API calls.
- 4
Test with your 30 free minutes
Every account starts with 30 free minutes. Run live test calls, listen via Listen Live, and use Barge In to take over mid-call while you tune the agent.
- 5
Go live and retire the component stack
Launch your campaigns or flip inbound routing over. There are no STT, TTS, or LLM vendor accounts to keep paying — one rate covers the whole pipeline.
Vapi Alternative FAQs
Common questions from teams evaluating Vapi and Phone Stack.
One rate. No stack to assemble.
Train your agent via chat and hear the ~320ms difference yourself. 30 free minutes, no card required.