AI invoicing · any country
Invoicing for your practice, your clinic or your firm, in any country and in your language, handled by an AI agent. Yours, or ours.
Billing record
F-2026/0412
Fingerprint (SHA-256)
3C1F8A07D2E94B6F 01A7E5C3B9D2…5B60A9E2
Chained to the previous one
F-2026/0411 · 9B7D…04C1
Tax QR code
Invoice verifiable on the AEAT
online portal · VERI*FACTU
Invoice
F-2026/0412
Marta Ferrer Gil
48291043-K
Open connector · MCP
Any AI agent can connect and run all of your invoicing: 38 operations, the same ones our built-in assistant has. It isn't a closed app with an assistant inside — it's your invoicing, with the door open.
It speaks MCP, the language your agent already uses, so it plugs into whatever you've set up without anyone coding a bridge.
// your agent, with its own credential
POST /api/connector/v1/documents
Authorization: Bearer fsp_·······
{ "customer": "Marta Ferrer Gil",
"lines": [ … ] }
201 · draft created
Each credential belongs to one company and can be read-only. Revoke it whenever you want.
Issuing is irreversible, so it goes through its own door, and who asked for it is logged.
Every operation carries its own retry key: if a response gets lost, nothing is invoiced twice.
Nothing to install. Choose your agent and click “Connect”: we take you to the screen where it goes, with the address ready to paste (in Claude, already filled in). Claude, ChatGPT and Grok ask you to log in (or create an account in a minute) and choose the company; Muse and AMUN, a key.
14-day free trial, no card required. You can cut the connection from the app whenever you want.
Once connected to your account, all 38 operations. Issuing waits until you complete your tax address.
Claude, ChatGPT, Grok and Muse are trademarks of Anthropic, OpenAI, xAI and Meta. FacturaSmart Pro connects to them but is not affiliated with any of them.
Connect with Claudeby Anthropic
The connector address
Claude’s free plan allows one custom connector. On Team and Enterprise, an organization owner adds it. Their official help
Don't have an agent? Two ways in. ClarIA comes built in and invoices for you — that's what you'll see below. And if you want a complete agent that, besides invoicing, runs your calendar, your email and your errands, AMUN Agent is ours: your personal agent on WhatsApp and Telegram, and it already knows how to talk to our apps, so it connects here on its own.
Meet AMUN Agent ↗ClarIA, our in-house agent
It's ready out of the box, nothing to connect. In the app's chat or on Telegram, with the same sentence you'd say to your accountant: it finds the customer, applies the VAT (IVA) your trade calls for and prepares the invoice.
Before issuing anything, it asks you. No invoice goes out until you say yes, and everything it does is logged.
Why this exists
If you run more than one company, you know the drill: log out, dig up the other password, log back in. And do it all over again every time you need to issue an invoice for the other one.
Not here. Add as many companies as you need under your account and switch between them without logging out. Each with its own tax ID, numbering series and invoice numbers, as it should be.
You pay per company, and the price per company drops the more you manage. An accounting firm with ten companies doesn't pay ten times the individual plan.
No logging out, no password per company.
In Spain · Veri*factu (AEAT)
Every invoice is signed with its own fingerprint, chained to the previous one, and goes out with its tax QR code printed on it. Neither you nor we can change it afterwards. Once you turn on submission, the record also goes to the Spanish Tax Agency.
If you make a mistake, you issue a corrective invoice. The way it's always been done, but without having to remember the rules.
Those are the dates when Veri*factu becomes mandatory. Here you invoice in that format from your very first invoice, so when the day comes there's nothing to migrate.
Invoice
F-2026/0412
Marta Ferrer Gil
48291043-K
Tax QR code
Invoice verifiable on the AEAT
online portal · VERI*FACTU
Every trade invoices differently
When you add your company, you choose what you do, and that sets up the VAT that applies to you, the units you measure in and the alerts for your industry. A clinic doesn't invoice like a shop.
VAT-exempt under article 20, with the exemption reason already filled in.
Services and sessions at 21%, with simplified invoices.
With income-tax withholding (IRPF) when the customer applies it.
Classes and courses, with whatever exemption applies.
With a heads-up about the equivalence surcharge if it applies to you.
Labor and parts on the same invoice.
Hospitality, transport and a few more. If yours isn't on the list, it invoices just the same.
A year of invoicing
Issued and received, sorted by numbering series and date.
Taxable base, VAT charged and paid, and what you owe.
For your accountant, in one file, whenever you want.
Pricing
14 days to try all of it, no card required. After that, €14.99 a month per company, and it drops the more companies you manage.
Get started — 14 days freeFrequently asked questions
Online invoicing software for freelancers and small businesses in any country: practices, centres, firms, shops and workshops. In Spain it issues with Veri*factu from the very first invoice. It keeps several companies under one account and comes with an artificial intelligence agent, ClarIA, that prepares invoices by chat or Telegram. It also connects to your own agent: Claude, ChatGPT, Grok or AMUN.
Yes. You add companies from any country: each one invoices with its country’s tax and its local name (VAT, GST, IGV…), with its date and address formats, and documents come out in Spanish, English or Arabic. In Spain it also handles Veri*factu, income-tax withholding and the VAT Act exemptions.
Yes. Every invoice is signed with its SHA-256 fingerprint, chained to the previous one, and printed with its tax QR code, as the Spanish invoicing systems regulation requires (Royal Decree 1007/2023). An issued invoice cannot be changed: mistakes are fixed with a corrective invoice. When you turn on submission, the record is also sent to the Spanish Tax Agency.
For companies, from 1 January 2027; for the self-employed, from 1 July 2027 (Royal Decree-law 15/2025). Here you already invoice in that format from the first invoice, so there is nothing to migrate when the date comes.
Yes. It has an open connector (MCP) with 38 operations: your agent signs in with your account, you pick the company, and it can add customers, prepare invoices or look up your figures. Issuing goes through its own door and records who asked for it, each connection can be read-only, and you can cut it off from the app at any time.
14-day trial with everything included and no card. After that, €14.99 a month per company, and the price per company goes down the more you have. Your data can always be exported, whether you pay or not.
Yes. You add as many companies as you need under one account and switch between them without logging out, each with its own tax ID, series and numbering. It is the usual case for accounting firms and for anyone with more than one company.
It is fixed with a corrective invoice, as the law requires: the original is neither deleted nor edited. The app prepares it from the wrong invoice, with its reason and reference.
When you add the company you choose your activity, and the VAT, units and warnings that apply come preset: healthcare exempt under article 20, beauty at 21%, professional services with income-tax withholding, training, retail with the equivalence surcharge, workshops and more. If your trade is not on the list, you invoice just the same.
Another product from MULTIPLE BRAND (FZE), the company behind ObraSmart Pro®.