Topcalls vs Synthflow: AI voice calling comparison (2026)
Last verified · by Topcalls Team
The verdict
Topcalls and Synthflow both let you build AI voice agents without heavy engineering. They price differently: Synthflow sells subscription tiers that bundle a block of minutes, with per-minute overage and telephony you connect or add on. Topcalls charges one $0.35/min all-inclusive rate billed by the second, so you pay for the minutes you actually use with telephony, recording, and transcription already inside that number.
Which one wins for your use case
| If you… | Pick | Why |
|---|---|---|
| want to pay only for the minutes you actually use | Topcalls | Topcalls bills $0.35/min by the second, with no monthly minute bundle to pre-purchase or waste. |
| prefer a monthly subscription with a set block of minutes | Synthflow | Synthflow packages minutes into tiered monthly plans, which can suit steady, predictable volume. |
| want telephony, recording, and transcription in one bill | Topcalls | All of it is included in the per-minute rate instead of being a plan tier or an add-on. |
| call across many countries and languages | Topcalls | Topcalls runs natural conversations in 32 languages with mid-call switching from a single platform. |
Feature comparison
| Feature | Synthflow | Topcalls |
|---|---|---|
| Pricing model | Tiered monthly subscription with bundled minutes plus per-minute overage | $0.35/min, all-inclusive and billed by the second |
| Telephony | Bring your own provider or add theirs | Included in the per-minute rate |
| Minute commitment | Plans bundle a block of minutes each month | No bundle; pay for what you use |
| Recording and transcription | Available depending on plan and configuration | Included for every call |
| Languages | Multiple, depending on the voice and speech models used | 32 languages with mid-call switching |
| Compliance tooling (TCPA, DNC) | Depends on how you configure the workflow | Built in: TCPA, TSR, DNC, GDPR |
| Integrations | Connects to common CRMs and automation tools | Native connections to 5,000+ apps |
Pricing
| Tool | Price | Notes |
|---|---|---|
| Synthflow | Tiered monthly plans with bundled minutes | Plans include a set block of minutes, with per-minute overage beyond it and telephony you connect or add. The effective cost per minute depends on the tier and how much of the bundle you use. |
| Topcalls | $0.35/min, all-inclusive | Voice model, telephony, recording, transcription, and analytics in one rate, billed by the second. No bundles, per-seat, or setup fees. |
When to pick Topcalls instead
Pick Topcalls when your volume moves around and you would rather not pre-buy a monthly block of minutes. Because billing is $0.35/min by the second, a slow week costs less and a busy one just adds minutes, with telephony, recording, transcription, and analytics already covered. Synthflow can be the better fit when your call volume is steady and a fixed monthly plan makes budgeting simpler. For teams calling across borders, Topcalls handles 32 languages with mid-call switching and ships TCPA, TSR, DNC, and GDPR controls in the product, so one platform covers multiple markets without extra configuration.
Frequently asked questions
Is Topcalls cheaper than Synthflow?
It depends on your volume. Synthflow bundles minutes into a monthly plan, so you pay for the block whether or not you use it. Topcalls is $0.35/min billed by the second, so you only pay for the minutes you actually place, telephony included.
Does Synthflow or Topcalls include telephony?
With Synthflow you typically connect your own telephony provider or add theirs. With Topcalls telephony is part of the per-minute rate, so there is no separate carrier bill to reconcile.
Can I use both Topcalls and Synthflow?
Yes. Some teams keep an existing Synthflow workflow running and move outbound campaigns to Topcalls for the all-inclusive per-minute billing, built-in compliance tooling, and single invoice.
How is the AI voice quality?
Both can sound natural. Topcalls ships tuned voices with sub-500ms response latency, so the conversation stays responsive without you assembling or tuning a provider stack.
Which fits better with my CRM?
Topcalls connects natively to your CRM and 5,000+ apps, so call outcomes sync back automatically. Synthflow integrates with common CRMs and automation tools as well; the difference is breadth and how much setup each takes.
How does compliance compare?
Topcalls enforces TCPA, TSR, DNC, and GDPR controls inside the product, including do-not-call dispositions and calling-hours rules. On Synthflow, compliance depends on how you configure the workflow.
See it on your own numbers
AI voice calling at $0.35/min, all-inclusive. No per-seat fees, no setup fees, no telephony markup.