# Phone Stack

> Phone Stack is AI call center software for inbound and outbound calls. Never miss a call: it replaces voicemail, not your receptionist. AI callers use native speech-to-speech (~320ms latency, powered by Google Gemini Live) so conversations sound human, with subscription plans from $69/month that include voice AI, telephony, recording, transcription, and integrations. Agents are trained through a zero-code chat interface and most teams launch in under 15 minutes. Supervisors can monitor any live call with Listen Live and take over with Barge In. Compliance tooling (TCPA-aware consent tracking, internal Do Not Call list with auto opt-out, calling-window enforcement, recording disclosure) is built in, and HIPAA-eligible deployments with a signed BAA are available as an add-on on Scale (contact us) and on Enterprise.

Try a live AI caller anytime: +1 (855) 49-STACK (+1-855-497-8225). Every new account starts with a free 14-day trial, no card required.

## Key facts

- Pricing: monthly subscriptions with included minutes. Starter $69/month (300 minutes included, $0.25 per extra minute, 1 location, 2 call flows). Growth $199/month, the most popular plan (1,000 minutes included, $0.20 per extra minute, 3 locations, 8 call flows, appointment booking, live transfer, SMS). Scale $399/month (2,250 minutes included, $0.18 per extra minute, 10 locations, unlimited call flows, waterfall transfer, HIPAA add-on available by contacting us). Enterprise from $1,799/month, contact sales for custom pricing. Annual billing is 10x the monthly price (2 months free). No per-seat fees, no setup costs. Phone numbers: $2/mo local, $10/mo toll-free.
- Free trial: 14 days free with Growth-level features and a 300-minute fair-use allowance, no card required.
- Never-Miss Guarantee: if a call goes unanswered because of a failure in Phone Stack's systems, we credit one month of service per verified claim. Details at https://phonestack.com/terms.
- Setup: zero-code, chat-based agent training: upload PDFs, paste a knowledge base, point at a website, or write a system prompt; preview the AI caller live before launch. First agent typically live in under 15 minutes; a full multi-campaign call center within a day.
- Voice: native speech-to-speech via Google Gemini Live (no STT-to-LLM-to-TTS chain), ~320ms response latency, natural barge-in handling, 30+ languages with native-quality voices.
- Modes: the same AI profile handles 24/7 inbound answering and outbound campaigns (lead qualification, meeting booking, appointment reminders, follow-ups, surveys, payment reminders) with one billing meter.
- Outbound features: campaign engine with contact-list dispatch, voicemail detection with personalized voicemail drops, phone-tree navigation (in-band DTMF), time-zone-aware calling windows, post-call emails/webhooks/CRM writeback.
- Supervision: Listen Live (silent monitoring of any active call) and Barge In (seamless human takeover).
- Integrations: native HubSpot two-way sync, Zapier (7,000+ apps), full REST API, webhooks (17 event types), MCP server for AI agents, and meeting booking on Google or Outlook calendars.
- Compliance: TCPA-aware consent tracking, internal Do Not Call list that auto-adds opt-outs, calling-window enforcement, recording disclosure controls. HIPAA Ready and SOC 2 Ready; a BAA is available with the HIPAA add-on on Scale (contact us) and on Enterprise. TLS 1.3 in transit, AES-256 at rest.

## Core product pages

- [AI Call Center Software](https://phonestack.com/ai-call-center): What an AI call center is, inbound + outbound capabilities, cost comparison vs traditional call centers and BPO, and FAQs.
- [AI Caller Software](https://phonestack.com/ai-caller): AI voice agents that sound human: voice quality, use cases (sales, support, scheduling, surveys, collections, healthcare), compliance, and a live demo number.

## Product and platform

- [Pricing](https://phonestack.com/pricing): All four plans with monthly and annual pricing, included minutes, extra-minute rates, and billing FAQs (14-day free trial, no contracts, no per-seat fees).
- [Features](https://phonestack.com/features): Full feature catalog covering voice, tools, compliance, and analytics.
- [How It Works](https://phonestack.com/how-it-works): How inbound and outbound AI calling works end to end.
- [Integrations](https://phonestack.com/integrations): HubSpot, Zapier (7,000+ apps), REST API, webhooks, and MCP server for AI agents.
- [Compare](https://phonestack.com/compare): Phone Stack vs Retell AI, Bland AI, Vapi, Air AI, and Synthflow on latency, pricing model, and setup.
- [Retell AI Alternative](https://phonestack.com/compare/retell-ai-alternative): One all-inclusive rate vs Retell's component pricing ($0.055/min base plus TTS and LLM costs); worked 3,000-minute cost example, feature table, and migration steps.
- [Bland AI Alternative](https://phonestack.com/compare/bland-ai-alternative): No monthly platform fees vs Bland's $299–$499/mo Build and Scale tiers; worked cost example, feature table, and migration steps.
- [Vapi Alternative](https://phonestack.com/compare/vapi-alternative): Predictable subscription pricing vs Vapi's $0.05/min orchestration base with a true cost of $0.07 to $0.25 per minute and a $1,000/mo HIPAA add-on; includes HIPAA cost scenario.
- [Synthflow Alternative](https://phonestack.com/compare/synthflow-alternative): One flat rate vs Synthflow's $0.15–$0.24/min published all-in with paid routing and latency add-ons; worked cost example and migration steps.
- [Security](https://phonestack.com/security): Encryption, infrastructure, subprocessors, HIPAA Ready and SOC 2 Ready posture.
- [API Documentation](https://phonestack.com/docs): REST API reference for calls, contacts, campaigns, profiles, reports, and webhooks.
- [Predictive Dialer](https://phonestack.com/features/predictive-dialer): AI predictive dialing for high-volume outbound.
- [Power Dialer](https://phonestack.com/features/power-dialer): Automated sequential outbound dialing.
- [Cell Phone Dialer](https://phonestack.com/features/cell-phone-dialer): Call into your AI dialer from any phone.

## Solutions

- [Solutions Overview](https://phonestack.com/solutions): AI calling solutions for reminders, follow-ups, payments, and property management.
- [Appointment Reminders](https://phonestack.com/solutions/appointment-reminders): Automated AI reminder calls that cut no-shows.
- [Follow-Up Calls](https://phonestack.com/solutions/follow-up-calls): AI follow-up call sequences for sales and service.
- [Payment Reminders](https://phonestack.com/solutions/collections): First-party invoice and past-due reminder calls.
- [Property Management](https://phonestack.com/solutions/property-management): Tenant and owner communications by AI phone.

## Industries

- [Property Managers](https://phonestack.com/property-managers-use-phone-stack): AI phone answering for property management companies.
- [Dentists](https://phonestack.com/dentists-use-phone-stack): AI phone answering for dental practices.
- [Doctors](https://phonestack.com/doctors-use-phone-stack): AI phone answering for medical practices.
- [Lawyers](https://phonestack.com/lawyers-use-phone-stack): AI phone answering for law firms.
- [Plumbers](https://phonestack.com/plumbers-use-phone-stack): AI phone answering for plumbing companies.
- [HVAC Contractors](https://phonestack.com/hvac-contractors-use-phone-stack): AI phone answering for HVAC companies.
- [Retailers](https://phonestack.com/retailers-use-phone-stack): AI phone answering for retail stores.
- [Case Studies](https://phonestack.com/case-studies): Industry-by-industry examples of Phone Stack in production.

## More product pages

- [AI Answering Service](https://phonestack.com/ai-answering-service): 24/7 live call answering by AI, a receptionist replacement.
- [AI Customer Service](https://phonestack.com/ai-customer-service): 24/7 tier-1 phone support that sounds human.
- [AI Phone Agent](https://phonestack.com/ai-phone-agent): Voice agents with tool use for inbound and outbound calls.
- [Automated Outbound Calling Software](https://phonestack.com/automated-outbound-calling-software): AI-driven outbound campaign automation.
- [Automated Customer Outreach Software](https://phonestack.com/automated-customer-outreach-software): Coordinated outreach across calls, emails, and webhooks.
- [Replace Your Call Center With AI](https://phonestack.com/replace-call-center-with-ai): Migration guide for moving call-center volume to AI.

## Blog: best resources

- [Best AI Call Center Software in 2026](https://phonestack.com/blog/best-ai-call-center-software-2026): Comparison of Phone Stack, Air, Bland, Synthflow, Retell, and Vapi with pricing, voice quality, and use-case fit.
- [AI Call Center vs BPO: Cost, ROI, and When to Switch](https://phonestack.com/blog/ai-call-center-vs-bpo): Per-call cost and quality math on AI vs traditional BPO contact centers.
- [AI Customer Service Cost Comparison: AI vs BPO vs In-House](https://phonestack.com/blog/ai-customer-service-cost-comparison): Real per-call cost math for AI phone support vs outsourcing vs in-house staff.
- [AI Call Center ROI Calculator: How to Model the Switch](https://phonestack.com/blog/ai-call-center-roi-calculator): Inputs, formulas, and worked examples for inbound and outbound ROI.
- [How to Build an AI Call Center (Step-by-Step Guide)](https://phonestack.com/blog/how-to-build-an-ai-call-center): Voice runtime, telephony, campaign engine, CRM sync, compliance, and analytics.
- [Replacing Your Call Center With AI: A 90-Day Plan](https://phonestack.com/blog/replacing-your-call-center-with-ai-90-day-plan): Pilot, cutover, and expand playbook for migrating call volume to AI.
- [AI Answering Service vs Virtual Receptionist](https://phonestack.com/blog/ai-answering-service-vs-virtual-receptionist): Cost and capability comparison vs traditional virtual receptionists.
- [What is an AI Caller? The Definitive 2026 Explainer](https://phonestack.com/blog/what-is-an-ai-caller): How AI callers work, what they can do, and why they matter.
- [Legal Framework for AI Calling: What's Allowed in the U.S. and Canada](https://phonestack.com/blog/legal-framework-ai-calling): Practical guide to TCPA, CASL, and CRTC rules for AI-powered calling.
- [AI Call Center for Small Business: A Practical 2026 Guide](https://phonestack.com/blog/ai-call-center-for-small-business): How small businesses use AI calling without hiring a team.

## Optional

- [Blog](https://phonestack.com/blog): All guides, comparisons, and playbooks on AI calling.
- [Contact](https://phonestack.com/contact): Book a demo or talk to sales.
- [Full plain-text content](https://phonestack.com/llms-full.txt): Concatenated plain-text version of the core pages and every blog post.