Synthflow: What It Is, Pricing, and Alternatives (2026)
Synthflow is a voice AI platform for building AI agents that answer and place phone calls at contact-center scale. It started as a no-code builder that small businesses and agencies could sign up for. In 2026 it sells to enterprises, on annual contracts.
The quick answer: Synthflow is a Berlin-based platform for designing, testing and running AI voice agents, with its own telephony network, a visual Flow Designer and automated QA on every call. Its pricing page lists one plan: Enterprise contracts from $30,000 a year, scoped around call volume, concurrency, telephony and integrations. If you want your business calls answered, and texts and email handled from the same team inbox, without a platform project, Carly is set up for you by the Carly team.
Synthflow at a glance
Checked against Synthflow’s website and pricing page on October 8, 2026. US dollars.
| Synthflow | |
|---|---|
| What it is | An enterprise platform to build, test, deploy and monitor AI voice agents |
| Channels | Voice first, plus chat, SMS and WhatsApp |
| Telephony | Its own network, or your SIP trunk and contact-center stack (Cisco, Avaya, Genesys, RingCentral) |
| Integrations | HubSpot, Salesforce, GoHighLevel, Cal.com, Zapier, plus APIs and webhooks |
| Scale | 65 million calls a month in 30+ countries, per Synthflow |
| Price | Enterprise contracts from $30,000 a year |
| Company | Founded in Berlin in 2023. Raised a $20 million Series A led by Accel in June 2025 |
| Best for | Contact centers, BPOs and enterprises automating high call volumes |
What Synthflow does
Synthflow packages the agent lifecycle into what it calls the BELL framework:
- Build. A visual Flow Designer defines each step of the call and connects your APIs. Subflows act as specialized agents inside one call.
- Evaluate. A Test Center runs simulated calls and scores accuracy, response quality and compliance against your targets before customers call.
- Launch. Agents run on Synthflow’s own telephony, which it says keeps latency under 100 milliseconds and uptime above 99.99%.
- Learn. Automated QA analyzes every live conversation and feeds the findings into the next version.
Around that sit versioned deployments you can roll back, real-time monitoring of calls, webhooks and API requests, and fine-tuning on your past calls. The use cases on its site are contact-center work: tier-1 support and overflow for BPOs, order tracking for retail, claims and caller verification for insurers, and property inquiries for real estate. Freshworks is its headline customer story, with 65% of voice workflows automated.
Synthflow pricing (October 2026)
| Plan | Price | What’s scoped |
|---|---|---|
| Enterprise | From $30,000 a year | Call volume, concurrency, telephony setup, integrations, security review, implementation and launch support |
That is the whole pricing page. There is no free tier or self-serve plan listed, and the homepage offers a demo rather than a signup. Synthflow used to sell self-serve plans to small businesses and agencies, and some third-party guides still describe them.
For context: a $30,000 contract is $2,500 a month before you know your volumes. The developer platforms below charge by the minute instead, and the ready-made receptionists charge a flat monthly fee.
Who Synthflow fits
Synthflow fits an operations team that already runs a contact center, has thousands of calls a day, and wants a vendor to own telephony, testing and QA as one system. Its enterprise integrations (Genesys, Avaya, Cisco) are the tell.
It is not built for a five-person company that wants missed calls answered next week. That buyer needs either a developer platform it can afford to experiment on or a service that sets the phone up for it.
Synthflow alternatives
| Alternative | Kind | Price |
|---|---|---|
| Carly | Calls, texts and email in one team inbox, with an AI receptionist, set up for you | Phone line priced on a short call. Free Zapier-style workflows; AI agents from $35/month |
| Vapi | Developer platform for voice agents | $0.05 a minute plus providers at cost |
| Retell AI | Developer platform for voice agents | $0.07 to $0.31 a minute plus telephony |
| Bland | Enterprise phone agent platform with a self-serve tier | From $0.14 a minute |
| Goodcall | Ready-made AI answering for small businesses | $79 to $299 a month |
1. Carly
Carly is the alternative for a business that wants its phones handled, not a voice platform to build on.
- One inbox for calls, texts and email, shared by the team, so every customer conversation is in one place.
- An AI receptionist that answers around the clock or after hours, qualifies callers, books them on the right calendar and hands off to a person when it should.
- Detects Spanish and answers in Spanish, with no phone menu.
- Calls new leads the moment they arrive from your web form, then emails your booking link and texts them if they miss it. Missed calls get a text back.
- Acts after the call: sends the follow-up, updates HubSpot, Salesforce or Carly’s own CRM, and keeps the summary and transcript on the record.
- Works from ChatGPT or Claude: add the Carly connector and ChatGPT or Claude can place calls and send texts on your team line, and build the voice and text agents from the chat (how it works).
The Carly team sets up your line with you, on your own Twilio line or a new number, and prices it on a short call. Everything else: free Zapier-style workflows; AI agents from $35/month.
2. Vapi
Vapi is the developer route: $0.05 a minute for hosting, plus the transcriber, model, voice and carrier at cost. Its calculator puts 1,000 minutes at $82 to $129. Your team builds and maintains everything.
3. Retell AI
Retell AI is the other big developer platform, at $0.07 to $0.31 a minute plus telephony, with no platform fee and $10 in free credits.
4. Bland
Bland is closest to Synthflow’s enterprise positioning but still sells self-serve calling at $0.14 a minute, or $0.12 plus $299 a month.
5. Goodcall
Goodcall is a ready-made AI answering service priced per unique caller, from $79 a month, for small businesses that do not want to build anything. See also AI voice agents.
FAQ
How much does Synthflow cost?
Synthflow’s pricing page lists Enterprise contracts from $30,000 a year. The final price depends on call volume, concurrency, telephony, integrations, security needs and launch support.
Does Synthflow have a free plan?
No free or self-serve plan is listed. The site offers a demo. For per-minute pricing you can try yourself, look at Vapi or Retell AI.
Is Synthflow no-code?
Its Flow Designer is visual, so you can build call flows without code, but connecting systems, testing and launch are scoped as an enterprise implementation.
What is the best Synthflow alternative for a small business?
Carly. It answers calls, texts and email from one team inbox, books, follows up and updates your CRM, and the Carly team sets it up with you. Book a call to scope your line.
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