If you looked at Synthflow a year or two ago, you may remember low monthly plans and warnings about paying separately for your own AI and voice provider keys. An earlier version of this post made that argument. It no longer applies. As of September 2026, Synthflow's pricing page lists enterprise contracts only, starting at $30,000 a year.
That puts Synthflow and ModPhone in different markets. Synthflow describes itself as an AI voice platform for enterprises, and it scopes each deal around call volume, phone infrastructure, integrations and security. ModPhone is an AI receptionist a small office can sign up for today, starting at $49 a month.
What Synthflow offers, as of September 2026
According to its pricing page, Synthflow prices each enterprise contract around call volume, concurrency, telephony setup, integrations, security needs and launch support. Contracts include:
- SLA and support terms written into the contract
- Synthflow's own telephony, SIP trunking, or approved enterprise telephony
- Planning for concurrent calls, routing, escalation paths and handoffs
- Integrations with CRMs, calendars, contact-center systems, webhooks, APIs and knowledge sources
- MSA and DPA support and an enterprise security review
- Implementation, onboarding, testing, training, launch support and ongoing optimization
Synthflow's site lists integrations including Cal.com, GoHighLevel, HubSpot, Salesforce and Zapier.
At $30,000 a year, the entry point works out to $2,500 a month. For a contact center moving thousands of calls off human agents, that can be a reasonable number. For a five-person accounting firm, a school's front office or a single-location auto shop, it is far more than the problem calls for.
What ModPhone offers
ModPhone's plans are self-serve and month to month:
| ModPhone plan | Price | Included each month |
|---|---|---|
| Starter | $49 | 200 minutes, 200 texts, booking, transfers, documents and website knowledge |
| Growth | $99 | 500 minutes, 500 texts, website chat, webhooks for Zapier, Make and n8n |
| Business (most popular) | $299 | 1,500 minutes, 1,000 texts, email agent, phone menus, HubSpot, GoHighLevel, Shopify |
| Enterprise | Custom | Unlimited numbers and volume, custom voices and languages, a dedicated success manager |
A year of the Business plan costs $3,588. The free trial runs 30 days and includes a US phone number, 100 minutes and 100 texts, with no card. Paid plans have a 30-day money-back guarantee.
Side by side
| Synthflow | ModPhone | |
|---|---|---|
| Built for | Enterprises automating phone operations | Small and mid-sized offices, schools and local government |
| Starting price (as of September 2026) | $30,000 a year | $49 a month |
| How you buy | Sales conversation and a scoped contract | Sign up online; Enterprise through sales |
| Who sets it up | Synthflow's implementation team, as part of the contract | You, from your website, in about 10 minutes |
| Phone infrastructure | Native telephony, SIP trunking or approved enterprise telephony | A ModPhone number, or forward your existing line |
| Channels | Voice agents; ask about other channels for your contract | Calls and texts on every plan, website chat from Growth, email on Business |
| Trial | Demo through sales | 30-day free trial |
Who should pick Synthflow
You run a large operation. You have a contact center, thousands of calls a week, an existing phone infrastructure you need to connect over SIP, and systems such as Salesforce the agent must work inside. You want a vendor to implement, test and keep tuning the agents for you, and your procurement process expects an MSA, a DPA and a security review. That is the buyer Synthflow's current pricing is written for.
Who should pick ModPhone
You want your calls answered and handled without a procurement project. ModPhone learns your business from your website and documents, and you can review and edit every fact it learned. It books into Google Calendar or Outlook and texts a confirmation, transfers to your staff or departments, texts callers a link mid-call, and emails your team a summary after each call. It speaks 30+ languages and switches mid-call.
A town clerk's office fielding after-hours calls about trash pickup and permit hours doesn't need SIP trunking or an implementation team. It needs the phone answered correctly tonight. See local government.
If you outgrow the self-serve plans, ModPhone Enterprise covers unlimited numbers and volume with a dedicated success manager, priced for your situation.
Common questions
How much does Synthflow cost?
As of September 2026, Synthflow's pricing page lists enterprise contracts starting at $30,000 a year, with the final price scoped around call volume, concurrency, telephony, integrations, security and launch support. It doesn't list self-serve monthly plans.
Does Synthflow still require your own API keys?
Its current pricing page doesn't mention bring-your-own-key costs, and pricing is set per contract. If this matters to you, ask Synthflow's sales team what the contract includes.
What is a Synthflow alternative for a small business?
For a small office that wants an AI receptionist without an enterprise contract, ModPhone starts at $49 a month, is set up from your website, and has a 30-day free trial with a real US phone number. Other self-serve AI receptionists exist too; compare what each one includes on its cheapest plan.
Can ModPhone handle a lot of calls?
Yes. ModPhone answers as many calls at once as come in, with no limit on simultaneous calls. The Business plan includes 1,500 minutes a month, and Enterprise covers unlimited numbers and volume. Greenville Humane Society handles more than 1,500 calls a month with ModPhone; see the case studies.
Try the self-serve route
Build an agent from your own website on the demo page; it takes about 30 seconds.