Every Unanswered Call
Costs You a Customer
Phone Stack plugs into your existing phone system and picks up when your team can't — on the 3rd ring, after hours, or when every line is busy. Not replacing your system or staff. Just zero missed calls.
Hear it for yourself — call our AI right now:
+1(855)49-STACKThe Hidden Cost of Your Ringing Phone
Every unanswered call is revenue walking out the door. Here's what the data shows.
62%
of calls to service businesses go unanswered
Industry average across SMBs
85%
of those callers never call back — they call your competitor
BrightLocal consumer survey
80%
drop in close rate if you don't respond within 5 minutes
Harvard Business Review
Do the math for your business
If you miss just 10 calls a week at a $300 average ticket, that's $156,000/year walking out the door.
Powered by frontier AI and communications providers
Claude
NVIDIA
MITPlugs Into Your Phone System.
Keep Your Team. Make More Money With Them.
Keep your current phone system. Phone Stack sits on top as a safety net — your team picks up when they can. AI catches every call they can’t, instantly. Everyone makes more money.
RingCentral
Vonage
8x8
Zoom
Dialpad
Grasshopper
HubSpot
Twilio+ any SIP/VoIP or landline system via call forwarding
Every Call Answered. Every Caller Helped.
Your AI answers in under a second, books appointments, handles questions, and routes emergencies — 24/7.
Sarah Martinez
Inbound — New Patient Inquiry
AI: "I have Thursday at 2pm or Friday at 10am available. Which works better for you?"
Sarah: "Thursday at 2 would be great, thanks."
Monitor Live. Review After.
The #1 reason businesses hesitate on AI calling: "What if it says the wrong thing?" Listen Live lets you monitor any call in real-time. Barge In lets you take over instantly. After the call, review full HD recordings, transcriptions, AI summaries, and outcome scores.
Other AI calling platforms
STT
LLM
TTS
~0ms typical latency — callers notice the pause
Phone Stack
Phone Stack AI
~0ms — callers can't tell it's AI
Why Callers Can't Tell It's AI
Most AI voice platforms stitch together three separate systems — each hop adds an awkward pause. Phone Stack uses native speech-to-speech processing: one model, one round-trip, natural conversation speed. Your callers hear a helpful, responsive voice — not a robot waiting to think.
2x faster than the next-closest platform
Your AI Gets Smarter With Every Call
A closed-loop system — every answered call makes the next one better
Train
Chat with your AI to teach it your business, objections, tone, and goals. Upload docs, set rules, define do's and don'ts.
Call
AI makes or answers calls using everything you taught it. Stereo recordings capture both sides at 24kHz quality.
Review
AI generates call summaries, scores outcomes, flags what went well and what didn't. Listen to recordings, read transcripts.
Refine
Update training based on real call data. Adjust tone, add rules, fix edge cases. Your AI improves with every campaign.
Your AI caller says what you mean and means what you say — because you trained it, reviewed it, and refined it.
Your AI Doesn't Just Answer — It Acts
Appointments booked, emails sent, leads routed — all while the caller is still on the phone.
Book Meetings
AI checks your calendar and books a slot while the contact is on the phone. Calendar invite sent instantly.
Send Emails
Confirmation emails, follow-ups, documents — sent during or immediately after the call based on conversation outcome.
Transfer to Human
When the AI reaches its limits, it transfers seamlessly to a live agent with full call context.
Trigger Webhooks
Update your CRM, create tickets, process payments, kick off workflows — all triggered by call outcomes in real time.
Connect to Everything
HubSpot
Native CRM integration. Log calls, create deals, trigger workflows.
REST API & Webhooks
18 API endpoints + real-time webhooks. Build anything.
MCP Server
40 tools for AI-native integrations. Works with Claude, ChatGPT, and any MCP client.
Campaign Analytics
Last 30 days1,247
Total Calls
73%
Goal Rate
3:18
Avg Duration
Every Call Becomes Intelligence
Aggregate insights across all your calls. See what's working, what's not, and where to optimize — without listening to a single recording.
Conversion trends
Track how many calls hit your goals across campaigns, agents, and time periods.
Outcome breakdowns
See goal achieved vs. missed at a glance — by campaign, time slot, or caller intent.
Custom reports
Slice data by any dimension: campaign, date range, outcome, duration, language.
Export & integrate
Download CSVs, pipe data through webhooks, or pull via REST API into your BI tools.
Built for Businesses That Answer Every Call
See how your industry stops missing calls
Patients call to book, reschedule, or ask about insurance. When nobody answers, they find a different provider.
Phone Stack answers every patient call instantly — schedules appointments, verifies insurance, handles after-hours triage, and sends confirmations. Your front desk focuses on patients in the office.
- Appointment scheduling and reminders
- Insurance verification before visits
- After-hours triage and routing to on-call
- Prescription refill coordination
- Post-visit follow-up calls
How the AI handles it
"Hi, I'd like to book a cleaning. Do you have anything next week?" → AI checks calendar, books Thursday at 2pm, sends confirmation text.
"It's 9pm and I'm having tooth pain." → AI triages urgency, routes emergency calls to on-call dentist.
"Can you check if my insurance covers this procedure?" → AI verifies eligibility and explains coverage.
Costs Less Than One Missed Customer
A single missed call can cost you $200–$2,000+ in lost business.
Starter
Test-drive AI calling risk-free before you commit
Starting at $15
- 60 minutes of AI talk time
- $15 one-time top-up
- One-time purchase, never expires
- Call recording, transcription & analytics
- Post-call emails, SMS & appointments included
- Consent tracking & opt-out handling
- Email support
Growth
The sweet spot where most teams see real ROI
Starting at $225
- 1,000 minutes of AI talk time
- $225 one-time top-up
- One-time purchase, never expires
- Everything in Starter
- Auto-refill when credits run low
- Priority support
Scale
Stretch every dollar as your call volume grows
Starting at $1,000
- 5,000 minutes of AI talk time
- $1,000 one-time top-up
- One-time purchase, never expires
- Everything in Growth
- API access
- Advanced analytics
Enterprise
Lock in our lowest rate with predictable costs
$1,800/mo commitment
- 10,000 minutes/month included
- Everything in Scale
- Dedicated CSM
- SSO/SAML
- SLA guarantee
- HIPAA & SOC 2 ready (BAA available)
Compliance-Ready Infrastructure. Every Plan.
HIPAA-ready and SOC 2-ready infrastructure on every plan, plus TCPA consent tracking and AES-256 encryption. Enterprise customers get signed BAAs and SOC 2 attestation reports.
They Stopped Missing Calls. Here's What Happened.
We were missing 40% of after-hours calls. Phone Stack picks up every one now — and our appointment bookings are up 35% in the first month.
Dr. Rachel Kim
Practice Owner, Bright Smile Dental
Our property managers used to spend half their day on the phone. Now the AI handles tenant inquiries and maintenance requests, and we haven't missed a prospective tenant call since we switched.
Marcus Rodriguez
Director of Operations, Apex Property Group
We tracked it — we were losing $12K/month to calls that went to voicemail. Phone Stack paid for itself in the first week.
Emily Watson
VP of Customer Success, NovaTech Solutions
Hear What Your Callers Will Hear
No lag. No robotic pauses. This is what "never miss a call" actually sounds like.
Sample: AI Answering an Inbound Call
Duration: 1:48 — A customer calls to book an appointment
Questions & Answers
Everything you need to know about stopping missed calls.
Never Miss a Call.
Every unanswered ring is a customer calling someone else. Phone Stack plugs into your phone system and catches every call your team can't. Hear it for yourself.