Fonoa Review
Fonoa is an API-first indirect tax platform for digital platforms, marketplaces and multinationals: it validates tax IDs, calculates VAT, GST and sales tax, clears e-invoices with tax authorities and prepares returns, sold by quote only.
Independently scored, one dimension at a time. Every dimension is sourced, and we say whether a claim is published, reported, or estimated.
The API docs set limits of 100 requests per second in production and 30 in demo, and Validate accepts 50,000 records per batch (checked 10 October 2026). Fonoa claims determination under 200 milliseconds and more than a billion transactions a year in its 28 May 2026 release, though its About page still says 500 million. Named customers include Uber, Netflix and Booking.com. Entity and user limits are not published.
Fonoa claims determination across 190+ jurisdictions, a figure its About page describes as countries and US states combined, plus tax ID validation in 120+ countries and e-invoicing mandates in 50+ countries (checked 11 October 2026). France's official list of accredited platforms and HMRC's Making Tax Digital software list both include Fonoa, and Fonoa says it is an accredited Peppol Access Point in Singapore. Other Fonoa pages cite 100+, 150+ and 200+ for the same products, and Returns has no public country list. Knowledge adds cited regulatory monitoring, and the Edge acquisition adds VAT and GST reporting that is still being integrated.
A hosted first-party MCP server at mcp.fonoa.com lists 16 tools, including tax calculation, tax ID validation and one write tool that submits e-invoices, with OAuth or API-key access (checked 11 October 2026). It has no public documentation or registry entry, and the Agents product that mentions MCP is marked Coming Soon. Fonoa Knowledge, an AI regulatory monitor with cited answers, launched 30 July 2026; its accuracy claims are the vendor's own.
Fonoa publishes no SLA or support tiers; help runs through a Zendesk request form and a support email in the API docs. Its site quotes G2 scores of 94 percent for quality of support and 97 percent for ease of doing business, plus a 4.6 of 5 Gartner Peer Insights rating (vendor-quoted, checked 10 October 2026). The Limehome case study mentions Slack support during migration, and Coda's describes a custom feature built during rollout.
Fonoa's site footer shows an AICPA SOC badge and an ISO/IEC 27001 Certified badge from the auditor Sensiba, and its security page names GDPR and third-party penetration tests (checked 11 October 2026). No public page says whether the SOC report is SOC 1 or SOC 2, or gives its type and period; ERP Research lists SOC 2 (reported), and Fonoa points buyers to a trust center. France's official list of accredited platforms includes Fonoa (registration dated 29 April 2026), and HMRC lists Fonoa Returns as recognised Making Tax Digital VAT software. The public terms for marketplace sellers (updated 9 May 2025) keep tax liability with the user and cap Fonoa's liability at 12 months of fees.
Go-live is an API project run by the customer's engineers, with a Fonoa solutions engineer configuring the account, per the e-invoicing quickstart (checked 10 October 2026). Vendor case studies cite four weeks for Coda's US tax engine and 26 working days for Limehome's Italian e-invoicing; Fonoa quotes a 50-day average for a first e-invoicing market. Sandbox and demo environments are documented, but API keys come from Fonoa and no prebuilt ERP connector shortens the work.
Everything runs through a REST API with webhooks and batch endpoints, plus a dashboard; the public reference covers Lookup, Tax and E-invoicing (checked 10 October 2026). Fonoa's site has no integrations or partner page and names no ERP or billing connector. ERP Research reports SAP, Oracle and NetSuite connectivity through the API with no marketplace listing evidenced. Wellhub's case study describes building its own Salesforce link.
Fonoa has no pricing page and sells every module by quote (checked 11 October 2026). Vendr's public page showed no median contract on 10 October 2026, only two buyer notes, and ERP Research describes usage-based pricing per module and transaction volume (reported). The only public fee terms are written for sellers on client marketplaces and allow fee increases on 30 days' notice; no enterprise rate card or order form is public.
Capable global VAT and e-invoicing plumbing for engineering-led teams; price and SOC proof sit behind sales.
Written by the Audit Friendly research team. No vendor edits, no sponsored placement.
You are buying tax infrastructure that your own engineers wire in. Fonoa sells four products on one data model: Validate (tax ID checks against government registries in 120+ countries), Tax Engine (VAT, GST and sales tax determination across 190+ jurisdictions, a count Fonoa's About page describes as countries and US states), E-Invoicing (mandates in 50+ countries; France's official list of accredited platforms has included Fonoa since 29 April 2026) and Returns. The public API reference covers the first three. Customers named by Fonoa include Uber, Netflix, Canva and Booking.com. A $110 million Series C and the purchase of PwC's Indirect Tax Edge, both announced 28 May 2026, fund the push into filing and AI (all checked 11 October 2026).
The catch is how much sits behind a sales call. There is no pricing page, and Vendr's public Fonoa page showed no median contract when read on 10 October 2026. The site footer carries an AICPA SOC badge and a Sensiba ISO/IEC 27001 Certified badge, and the security page names GDPR, but no public page says whether the SOC report is SOC 1 or SOC 2, its type or its period; buyers are pointed to a trust center (checked 11 October 2026). No prebuilt ERP or billing connector is documented, so SAP, NetSuite or Stripe data reaches Fonoa through an API build. Coverage counts differ from page to page, Returns has no public country list, and the Agents product is marked Coming Soon.
Before signing, get in writing: the fee unit for each module and the overage rate past committed volume, the SOC 1 and SOC 2 report types and periods, the countries where Fonoa files returns and clears e-invoices itself and those handled by a third-party processor, how long issued invoices are archived (Fonoa's public terms for marketplace sellers say up to 18 months), the cap on renewal uplift, and an export of transactions, invoices and validation history on exit.
- A marketplace or digital platform that must validate seller and buyer tax IDs at onboarding and issue e-invoices on behalf of sellers in many countries.
- A multinational SaaS or payments company with engineers available that wants determination, e-invoicing and returns on one API in place of several regional vendors.
- A tax team facing new e-invoicing mandates, such as France from September 2026, that wants one integration to cover each country as it goes live.
- A US-only seller that wants per-state sales tax filing at a published price; Avalara and Anrok publish plans and Fonoa sells by quote.
- A finance team with no engineering support that expects a native NetSuite, SAP or QuickBooks connector; none is documented.
- Buyers whose procurement needs a public SOC 1 Type 2 statement and list pricing before a first call.
The jobs a tax team actually hires Fonoa for
Jobs, mapped to how finance teams actually buy.
Validate tax IDs at onboarding and checkout
Validate checks a customer, supplier or seller tax ID against government registries and returns the registered name and address with the result. Batches take 50,000 records, and a name search finds a missing ID. Instant Validate added sub-second checks from pre-validated data for France, Germany and Spain in July 2026, according to Fonoa.
Calculate VAT, GST and sales tax in real time
Tax Engine returns the tax treatment for a transaction from supplier, customer and line-item data, including marketplace and cross-border cases. Fonoa claims responses under 200 milliseconds and built-in tracking of registration thresholds. Coda's case study reports calculations 90 percent faster than its prior engine (vendor-claimed).
Clear e-invoices with tax authorities from one API
One transaction payload is translated into each country's format and submitted to the tax authority, with the result returned by webhook. Fonoa says it is a certified Accredited Platform for France and an accredited Peppol Access Point in Singapore. Limehome's case study cites a 99.9 percent invoice acceptance rate (vendor-claimed).
Prepare and submit VAT returns
Returns populates local VAT, GST and sales tax forms from transaction data, runs validation checks and submits to tax authority portals in supported jurisdictions. It can pull cleared e-invoice data so periodic filings match what was reported in real time. Fonoa says the product is recognised by HMRC for Making Tax Digital for VAT.
Report platform sellers under DAC7
Data Sharing structures seller data, checks it for completeness, formats the XML report and generates seller notifications. Fonoa says it does not store the sensitive data it processes for this product. It suits marketplaces that already collect seller tax IDs through Validate.
Monitor regulatory change with cited answers
Knowledge, launched 30 July 2026, tracks indirect tax changes, ranks them against a company profile and answers questions with citations to primary sources, according to Fonoa. Alerts can be routed to chosen people. The product is new, and no independent accuracy test was found.
Watch the same task in each tool
Forget the 40-row feature grid. Pick a finance workflow and see how this tool and its closest peers actually do it, with our verdict on who wins for whom.
Compare on what matters
What it actually costs
Here's what it really costs: published rates where a vendor lists them, aggregated quote data where they don't, plus a path to your own number.
Real-time and batch tax ID checks against government registries in 120+ countries, with name search and fuzzy matching. Listed as Lookup on Vendr and in the API docs.
Real-time VAT, GST and sales tax determination through the API, with configurable rules and threshold monitoring. Named Fonoa Tax in the API docs (checked 11 October 2026).
Submission of invoices and transaction reports to tax authorities for accounts receivable and accounts payable, plus compliant PDF documents. Country scope is set per customer by Fonoa.
Preparation, validation and submission of VAT, GST and sales tax returns in supported jurisdictions, with a workflow tracker for deadlines and owners.
AI regulatory monitoring with cited answers (launched 30 July 2026) and plain-language audit queries over transaction history. Both are labeled New; packaging is not published.
Charged on overdue amounts under Fonoa's public terms of service (last updated 9 May 2025), which are written for sellers invoicing through a client marketplace. The same terms allow fee increases on 30 days' notice. An enterprise order form may differ.
What it actually takes to go live
The Tax Engine page claims 190+ jurisdictions, the home page says 100+, the Agents page says 150+ and a solutions page says 200+ countries (all checked 10 October 2026). Validate is 120+ countries on its product page, 100+ in the 28 May 2026 press release and 110+ or 115+ elsewhere. E-invoicing is 50+ countries with mandates on the product page and over 150 countries on a solutions page. Annual volume is 500 million transactions on the About page and more than a billion in the May release. Ask for the country list per product, with the status of each.
Fonoa has no pricing page, rate card or fee schedule on its site (checked 11 October 2026). Vendr's public Fonoa page showed no median contract value when read on 10 October 2026. Its two buyer notes describe a 50 percent reduction from the first quote and better terms for a multi-year deal with case-study rights (reported). Expect a wide gap between first quote and signed price, and bring a competing offer.
Fonoa's site has no integrations or partner page, and its API reference covers Lookup, Tax and E-invoicing endpoints only (checked 10 October 2026). ERP Research reports that SAP, Oracle and NetSuite connectivity is delivered through the REST API with no SAP Store, Oracle marketplace or SuiteApp listing evidenced (reported, updated August 2026). Wellhub's case study describes building its own service to call Fonoa from checkout and from Salesforce. A finance team without engineers will need a partner or middleware.
Fonoa's public terms of service (last updated 9 May 2025) cover sellers who invoice through a client marketplace on Fonoa's older invoicing sites, so treat them as a guide to what an enterprise buyer may be offered. They say issued invoices are stored for up to 18 months, that this may fall short of local archiving rules, and that on termination a backup must be requested within 10 days at the user's cost. They leave responsibility for invoice content with the user, cap Fonoa's liability at 12 months of fees and apply Croatian law. A separate amendment to a marketplace standard contract on Fonoa's legal pages (page dated 13 May 2025) sets Irish law, Dublin arbitration, a 12-month liability cap and one-year auto-renewal with 60 days' notice. Negotiate retention, exit and uplift terms into the order form (checked 11 October 2026).
The site footer carries an AICPA SOC badge and an ISO/IEC 27001 Certified badge from the auditor Sensiba, and the security page lists GDPR compliance, encryption and third-party penetration tests (checked 11 October 2026). No public page says whether the SOC report is SOC 1 or SOC 2, its type or its period. ERP Research lists SOC 2 and ISO 27001 for Fonoa (reported). A tax engine feeds the financial statements, so ask for the SOC 1 Type 2 report, or the alternative your auditors will accept, through the trust center at trust.fonoa.com.
Fonoa Returns has no public country list; its pages name HMRC recognition for UK Making Tax Digital, and a case study mentions the Netherlands, Finland and Mexico (checked 10 October 2026). On 28 May 2026 Fonoa bought Indirect Tax Edge from PwC, a VAT and GST reporting and e-filing system, and said it will integrate it with the platform. PwC continues to deliver services on Edge. Ask which product will file in each country, and what the migration path is if the two are merged.
Scored on what an outside agent can actually reach: the documented API, how it authenticates, and whether the vendor ships an MCP server.
Exists: On 10 October 2026 mcp.fonoa.com/mcp answered an MCP initialize as server fonoa-tax, version 1.0.0, and returned its tool list without credentials. The only public mention is one line on the Agents page, which is labeled Coming Soon and says AI tools can call Agents through MCP. No MCP article appears in docs.fonoa.com, and the official MCP registry lists no Fonoa server. A second endpoint, docs.fonoa.com/mcp, belongs to the documentation portal.
Scope: The server lists 16 tools. Fifteen are marked read-only: single and batch tax ID validation, reverse lookup of a tax ID by company name, tax calculation, a compliance summary, e-invoice transaction lists and details, error breakdowns and error documentation. One, submit_transaction, is marked destructive: it submits an e-invoice to a tax authority, and its own description calls the action irreversible in most countries and asks for user confirmation first. Nothing covers returns, account configuration or Knowledge.
Turnkey: The server publishes OAuth metadata pointing at api.fonoa.com with PKCE and client ID metadata documents, so an MCP client can run a browser login without a pre-registered app. Its instructions say Fonoa API keys are also accepted in a header. With no setup guide, tool reference, stated limits or availability label, treat it as live and unsupported until Fonoa documents it. The docs-portal server adds endpoint search and a generic execute-request tool that sends whatever API request the caller supplies, key included.
In-product AI: Fonoa Knowledge, launched 30 July 2026, monitors indirect tax changes and answers questions with citations to primary sources, according to Fonoa. Audit, labeled New, adds plain-language queries over transaction history and an AI confidence score. Agents, which Fonoa says will populate returns and trigger registration workflows with human approval, was still marked Coming Soon on 10 October 2026. No independent test of answer accuracy was found.
Fonoa, kept current
As of 10 October 2026 the Agents page carried a Coming Soon label, while a hosted MCP server at mcp.fonoa.com already listed 16 tools. No documentation or launch post was public.
Fonoa's update on July 2026 releases: sub-second VAT number checks from pre-validated data in three EU markets, accreditation as an InvoiceNow Peppol Access Point in Singapore, and accounts payable support for Romania.
An AI regulatory intelligence product that monitors indirect tax changes, maps them to a company profile and answers with citations to primary sources, according to Fonoa.
Headline led the round, with Eurazeo and Forestay Capital joining Index Ventures, OMERS, Coatue and Dawn Capital. Edge adds VAT and GST reporting and e-filing; PwC keeps delivering services on it.
Fonoa said it is a certified Accredited Platform (PA), able to issue, transmit and receive Factur-X, UBL and CII invoices and to handle e-reporting ahead of the 1 September 2026 start date.
Fonoa's newsroom reported a fourth straight appearance on Sifted's list of fast-growing European B2B SaaS companies.
Fonoa FAQ
Fonoa does not publish prices, and no public benchmark gives a median (checked 10 October 2026). Validate, Tax Engine, E-Invoicing and Returns are each quoted, and ERP Research describes the model as usage-based per module and transaction volume (reported).
The only public datapoints are two buyer notes on Vendr from companies with 201 to 1,000 employees. One used a lower Avalara offer to bring the Fonoa agreement down to 50 percent of the original quote. The other got its best terms through a multi-year agreement plus case-study rights (reported; undated).
Budget for the build as well as the license. Fonoa is integrated through its API by the buyer's engineers, and no prebuilt ERP connector is documented. Ask for the overage rate on validations and transactions above the committed tier, since no public page states it.
No enterprise master agreement is among Fonoa's public legal pages. The public terms of service (last updated 9 May 2025) are written for sellers who invoice through a client marketplace on Fonoa's older invoicing sites: the user owns its invoice data, paid add-ons are non-cancellable and non-refundable, fees can rise on 30 days' notice, liability is capped at the fees paid in the prior 12 months, and Croatian law governs with arbitration in Zagreb. A separate amendment to a marketplace standard contract (page dated 13 May 2025) sets Irish law, arbitration in Dublin, a 12-month liability cap that rises to three times fees for a security breach, and one-year auto-renewal unless notice is given 60 days before the term ends. Ask which paper applies to the deal and compare the signed version (checked 11 October 2026).
On data, the public terms of service say issued invoices are stored for up to 18 months and that Fonoa's storage may fall short of local archiving rules. On termination, invoice data is deleted; a backup must be requested within 10 days and is delivered at the user's cost. Pull transactions and validation results through the API's GET endpoints on a schedule and keep your own archive.
The buyer's engineers do most of it. Fonoa is API-first: the team calls the Lookup, Tax and E-invoicing endpoints from checkout, billing or invoicing code and listens for webhooks. A Fonoa solutions engineer sets up the product configuration, and API keys are issued by Fonoa after onboarding (docs, checked 10 October 2026).
Vendor case studies give a range. Coda's US tax engine took four weeks of active work, Limehome went live with Italian e-invoicing in 26 working days, and an unnamed AI infrastructure group had Validate integrated in two weeks. Fonoa quotes a 50-day average for a first e-invoicing market and says later markets go faster (all vendor-claimed).
Plan for data work first. Booking.com Transport's story describes centralizing tax data from reservation and finance systems before the integration. A sandbox with simulated tax authority responses lets the team test before production.
Partly, and through an endpoint Fonoa has not documented. On 10 October 2026 a hosted MCP server at mcp.fonoa.com listed 16 tools: tax ID validation, tax calculation, e-invoice transaction lookups, error diagnostics and one write tool that submits an e-invoice to a tax authority. It accepts an OAuth login or a Fonoa API key.
There is no public setup guide, tool reference or support statement, and the Agents product that mentions MCP is labeled Coming Soon. Treat the server as early access and ask Fonoa whether it is supported for production. The documented route is the REST API, which an agent can call with a subscription key.
No tool covers returns, rule configuration or Knowledge. An agent can check IDs, compute tax and investigate failed invoices today; filing and approvals stay with people.
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