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  • Administration
    • Account Access & Login
      • Overview
      • Usage
      • Pay As You Go
      • Enterprise
      • Manage your Subscription
    • Early Access Program
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On this page
  • What’s included
  • How PAYG billing works
  • Add-ons
  • Concurrency
  • White-label toolkit
  • Phone numbers
  • Coming soon
  • When to consider Enterprise
  • FAQ
AdministrationBilling

Pay As You Go

Usage-based pricing with no commitments

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Enterprise

Enterprise-grade reliability, scale, and support

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Built with

Pay As You Go (PAYG) is designed for builders, pilots, and small-scale deployments. Explore the platform at no cost, then pay only for the calls and chats you make.

What’s included

Every PAYG workspace includes:

FeatureIncluded
Base price$0/month
Per-minute rate$0.15–0.24
Concurrency units5
Log retention1 month
API rate limit30 requests/minute
SupportCommunity + ticketing
ComplianceSOC2, GDPR, ISO 27001

You also get full access to the Synthflow Academy and community forum.

How PAYG billing works

Once you add a payment method, your workspace is subscribed to the PAYG plan at $0.00 per month. You’re only charged when you:

  • Make phone calls with your agents
  • Use chat agents
  • Purchase add-ons

Call billing has two parts: LLM-based billing (the rate depends on which language model you use) and the voice engine (your transcriber and synthesizer providers). Combined, effective rates typically fall between $0.15–0.24 per minute depending on usage and destination. Learn more about how usage is calculated.

In practical terms, PAYG is best when you want low commitment and predictable access to the product, while accepting that your exact spend scales with call volume, model choice, and telephony usage.

Once your balance reaches US$200, we’ll charge your card and send you an invoice. This keeps charges manageable instead of building up over time.

Add-ons

Expand your workspace capabilities with add-ons available in Settings > Add-Ons.

Concurrency

PAYG includes 5 concurrency units by default, allowing up to 5 simultaneous calls. Additional units cost $20 per month each.

Scale concurrency as your volume grows without renegotiating contracts or changing plans. This is ideal for businesses with fluctuating call volumes or seasonal spikes.

Learn more about call concurrency.

White-label toolkit

The white-label toolkit is available for $2,000 per month. It enables:

  • Custom branding and domains
  • Subaccount management
  • Client-facing dashboards
  • Rebilling capabilities

This add-on is designed for agencies reselling Synthflow to their own clients.

Learn more about agency and white-labeling.

Phone numbers

Purchase phone numbers directly in the Phone Numbers page. Options include:

  • Local numbers
  • Toll-free numbers
  • International numbers

Each number costs $1.50 per month plus per-minute charges for calls. Review pricing before confirming and assign numbers to specific agents.

Learn more about purchasing phone numbers.

Coming soon

We’re expanding the PAYG add-on catalog to include:

  • Alternative voice engines
  • LLM routing options
  • Global edge deployments
  • Additional telephony providers

When to consider Enterprise

PAYG works well for most use cases, but you may want to consider Enterprise if you need:

  • High volume: 10,000+ minutes per month
  • Guaranteed uptime: 99.99% SLA
  • Unlimited concurrency: No per-unit charges
  • Dedicated support: Named account manager
  • Custom integrations: SIP trunking, custom workflows
  • Custom pricing: Volume discounts and committed rates

Compare plans on our pricing page or contact sales to discuss your requirements.

FAQ

Is there a free trial?

There’s no time-limited trial. You can explore the platform, build agents, use the flow designer, add knowledge bases, and preview voices without a payment method. Once you add a payment method and start making calls or using chat, usage-based charges begin.

What's the minimum commitment?

None. PAYG is month-to-month with no contracts. You can cancel anytime from the Billing Portal.

Can I upgrade to Enterprise later?

Yes. Contact our sales team to discuss upgrading. Your usage history and agents transfer seamlessly.

How do I add more concurrency?

Go to Settings > Add-Ons and purchase additional concurrency units at $20/month each.

Is white-labeling available on PAYG?

Yes. The white-label toolkit is available as a $2,000/month add-on. You don’t need Enterprise to white-label.

What happens if I exceed my concurrency limit?

Additional calls will be queued or may fail to connect. Monitor your concurrent call usage and add more units if you regularly hit limits.

Can I get volume discounts on PAYG?

PAYG has standard rates. For volume discounts and committed pricing, consider the Enterprise plan.