Last verified October 10, 2026.
Details about Synthflow come from its public pages as they were on October 10, 2026. Synthflow may have changed them since, and a page that was unclear to us may be clear to you. Corrections: support@calldesk.tech. We make Calldesk, so read this page with that in mind and check anything important with Synthflow directly.
About Synthflow
How Synthflow positions itself: A voice and chat agent platform with a no-code Flow Designer and Prompt Builder, now selling mainly through sales-scoped enterprise contracts, with agency subaccount and rebilling features.
Side by side
A row is shown when we could read both sides. Where Synthflow's pages did not say, a cell reads "not stated on the pages we reviewed" rather than a guess. It rests on published pricing, setup and wording, and does not use call-quality or benchmark results.
| Topic | Calldesk | Synthflow |
|---|---|---|
| How pricing works | Per minute of call time on three plans: Lite 2¢, Standard 5¢, Pro 9¢. No monthly minimum. Phone carrier charges are billed separately. | Sales-led enterprise contracts scoped to call volume, concurrency, telephony and support; no self-serve price list was found on the public pricing page. (source: synthflow.ai) |
| Published starting price | 2¢ to 9¢ per minute depending on the plan, before phone carrier charges | Enterprise contracts start at $30,000 per year per the vendor's pricing page; no public per-minute rate. (source: synthflow.ai) |
| Bring your own carrier | Yes, on every plan, at no extra charge, by forwarding calls to a number you register (no SIP trunking) | Yes (source: docs.synthflow.ai) |
| Phone numbers from the provider | A paid extra on every plan: Telnyx $1.00 per month per number plus 1 cent per inbound minute; Twilio $2.00 per month per number plus 1.5 cents per inbound minute. Registering a number you already own costs nothing extra. | Numbers can be bought in Synthflow for the U.S., Canada and Australia; Twilio accounts and SIP trunks (Enterprise) are supported. (source: docs.synthflow.ai) |
| HIPAA | Not claimed | Stated on their pages (source: docs.synthflow.ai) |
| SOC 2 | Not claimed | Stated on their pages (source: docs.synthflow.ai) |
| GDPR | Not claimed | Stated on their pages (source: docs.synthflow.ai) |
| Integrations and developer tools | REST API, MCP server and signed webhooks, plus calendar booking | Twilio, SIP trunks and PBX (Telnyx, Vonage, RingCentral, 8x8, Zoom, Five9, 3CX and others), Salesforce, HubSpot, GoHighLevel, Cal.com, Zendesk (Help Center import), Zapier, Stripe (agency rebilling), WhatsApp and Webhooks and MCP servers |
About Synthflow's compliance wording: Stated by vendor, self-attested: the homepage says infrastructure is certified across SOC 2, HIPAA, PCI DSS and GDPR; docs publish a BAA template (executed at contract signing for customers using the HIPAA setting) and agent-level retention/PII controls. No audit report was seen.
Synthflow pricing details
- Docs state Synthflow uses sales-led pricing and that public documentation should not be used as a quote. (source: synthflow.ai)
- Some existing workspaces may still show legacy billing labels governed by their own agreement. (source: synthflow.ai)
- Enterprise includes custom concurrency planning, telephony setup (Synthflow native telephony, SIP trunking or approved telephony), integrations, MSA/DPA support, onboarding and launch support. (source: synthflow.ai)
What Synthflow does well
- No-code agent building with a Flow Designer and Prompt Builder, templates, and JSON import for agent configurations. (source: docs.synthflow.ai)
- Agency-oriented features: subaccounts, limits per subaccount, and Stripe-based rebilling and pricing plans for reselling. (source: docs.synthflow.ai)
- Operator-grade telephony tooling: regional infrastructure (Global, US, EU), SIP call ladder diagrams with PCAP download, and documented SIP integration with many carriers and PBX systems. (source: docs.synthflow.ai)
- Compliance posture stated for enterprises: SOC 2, HIPAA, PCI DSS and GDPR on its site, a published BAA template, agent-level retention and PII redaction controls, and an EU AI Act transparency statement. (source: docs.synthflow.ai)
- Large stated scale: the vendor reports more than 65 million voice calls per month across 30+ countries and WhatsApp calling support. (source: synthflow.ai)
Conditions to check with Synthflow
These are limits or conditions described on the pages we reviewed. We list them so you can check whether they matter for your calls.
- SIP/PBX integration requires an Enterprise plan subscription. (source: docs.synthflow.ai)
- Pricing is sales-scoped; enterprise contracts start at $30,000 annually and no public per-minute or self-serve plan pricing was found. (source: synthflow.ai)
- Numbers bought inside Synthflow cover the U.S., Canada and Australia; the docs recommend Twilio or SIP for production use. (source: docs.synthflow.ai)
Where Calldesk is different
- Billing: Calldesk bills one per-minute rate for the plan you choose (Lite 2¢, Standard 5¢ and Pro 9¢ per minute), with the phone carrier billed separately. We did not find a list of separate charges on Synthflow's pages, so ask Synthflow what a month at your volume would include.
- Phone setup: both support bringing your own carrier. With Calldesk you register a number you own and forward calls to it. Calldesk does not offer SIP trunking, which Synthflow's pages describe. Calldesk also sells numbers from Telnyx and Twilio if you prefer not to bring one.
- Languages: Calldesk supports 40+ languages, including English; agents in a language other than English need the Standard or Pro voice, because the Lite voice speaks English only.
- Developer tools: Calldesk has a REST API, an MCP server and signed webhooks for call.completed, call.transferred and call.analyzed events (/docs).
- Compliance: Calldesk does not currently claim any compliance certification, so if your industry requires one, ask us what we can show you before you rely on it.
Which one fits
Synthflow may suit you if this describes you: enterprises and agencies that want a no-code builder with a vendor-led rollout and scoped contracts rather than self-serve per-minute pricing.
Calldesk may suit you if your calls match one of its plans. Lite is for straightforward calls such as confirmations and quick questions, where cost matters most. Standard is for most businesses: reception, booking, intake and after-hours coverage. Pro is for complex or high-stakes calls where reasoning and tone matter most. Current prices are on the pricing page at /pricing.
What we could not confirm about Synthflow
- No public per-minute price or self-serve plan list found; earlier self-serve plans may exist for legacy accounts (docs mention legacy billing) but are not published.
- Free trial availability not stated on pages read.
- Compliance certificates were not seen; claims are from the vendor's homepage.
- Whether SIP/Twilio details differ for existing legacy workspaces is unclear.
- Agent export format (beyond the API read and JSON import) was not verified.
Sources
- Synthflow pricing page (retrieved October 10, 2026)
- Synthflow docs: Billing Overview (retrieved October 10, 2026)
- Synthflow docs: Telephony (retrieved October 10, 2026)
- Synthflow docs: Security & Compliance (retrieved October 10, 2026)
- Synthflow docs: Business Associate Agreement (retrieved October 10, 2026)
- Synthflow docs: Create an Agent (retrieved October 10, 2026)
- Synthflow homepage (retrieved October 10, 2026)
- Synthflow docs index (retrieved October 10, 2026)
- Synthflow docs: Pricing plans and Rebilling (retrieved October 10, 2026)
- Synthflow docs: Export Call Data (retrieved October 10, 2026)