Request your invoice on WhatsApp.
Get it in seconds.
ContaGPT is your CFDI 4.0 invoicing assistant on WhatsApp. Type or send a voice note — "invoice Ramiro for December rent" — and we issue, stamp, and send it back in chat. No SAT portal, no apps, no catalogs.
Four steps. Zero SAT portals.
You talk to ContaGPT like a person. If you've invoiced that customer before, we remember their details and suggest them automatically.
Message us
By text or voice: "invoice Ramiro for December rent." We understand it like a person.
Confirm with one tap
We only ask what's missing and give you WhatsApp buttons to confirm, edit, or choose — no catalogs, no codes.
Preview
We show a draft so you confirm before stamping. If something's wrong, we fix it on the spot.
Receive XML and PDF
We stamp with an authorized PAC and send the files on WhatsApp. Ready to forward to your customer.
Everything invoicing needs,
without leaving WhatsApp.
Invoices, payment complements, cancellations, schedules, templates, and tax questions — all in one conversation.
Income invoices
CFDI 4.0 type I for sales, services, fees, and rent. PUE or PPD depending on how you get paid.
Payment complements
When you receive payment on a PPD invoice, we issue the complement (REP) without you having to remember the rules.
Cancellations
We guide you through SAT motives. Substitution, error, or other — we link the new CFDI to the original.
Scheduled invoices
"Every 1st of the month, invoice Ramiro's rent." We schedule it and it goes out on its own.
Customer memory
If you've invoiced someone before, their tax details are suggested automatically. You don't ask twice.
Live tax Q&A
"When do I use PPD?" "Which CFDI use codes applies?" We answer based on the current SAT guide.
Generic RFC (general public)
Customer has no RFC or won't share it? We issue to XAXX010101000 with the correct fields.
Multi-RFC
Running several companies or activities? Register all your RFCs and switch between them with a message.
Pre-stamp validation
We check CFDI use, tax regime, and postal code to avoid the errors the SAT rejects most often.
VAT, IEPS, and withholdings
We compute the taxes that apply to you based on your regime and your customer's. You don't have to remember the rates.
Line-item templates
What you always invoice the same way — the rent, the monthly retainer — is saved as a template. Call it by name and you're done.
We email it to your customer
Give us their address and the invoice lands in their inbox with XML and PDF. You stop forwarding files.
What happens
without you asking.
While you invoice, ContaGPT keeps your tax information organized, current, and within reach — for you and for your accountant.
A web dashboard with your numbers
Open it in your browser and review invoices issued and received, your VAT and income tax for the month, and your credit balances.
Your Constancia, always current
We pull your Constancia de Situación Fiscal straight from the SAT and keep it valid for you. No portal visits, no sending it to us.
Renewed every 30 daysYour Opinión de Cumplimiento, kept current
The 32-D you're asked for to contract with the government or onboard as a supplier to a large company. We generate it for you and tell you whether it came back positive or negative.
Renewed every 30 daysYou and your accountant, one account
You both see the same invoices and the same dashboard, and if you authorize it your accountant can invoice on your behalf too. No more XMLs by email, no more "did you already invoice this?". You choose which RFC they see and can revoke it anytime.
Your history is already in there
When you sign up we download your issued and received invoices for this year and last year from the SAT. Your dashboard doesn't start empty.
If a supplier cancels on you, you'll know
We check your received invoices against the SAT. If someone cancels one you were going to deduct, we tell you on WhatsApp.
We support the most common regimes in Mexico.
Not sure which one applies to you? Message us on WhatsApp and we'll help you figure it out.
Don't see yours? Ask us — the list keeps growing.Your channel is already WhatsApp.
Your invoicing can be too.
It's not another invoicing portal. It's an assistant that lives where you already are, talks like you do, and learns from every invoice you issue.
Natural conversation
No menus, no SAT codes. "Invoice Ramiro" is enough. We only ask what's missing.
Learns from your history
Already invoiced a customer? We remember their details. Sell something recurring? We suggest it automatically.
Available 24/7
Need an invoice Saturday at 10 pm? Issue it in 30 seconds without opening your laptop or calling anyone.
What people ask us most.
How do I sign up?
We're in private beta and only work with approved users for now, so everyone gets a great experience from the first message. Send us a WhatsApp and we'll reach out to walk you through onboarding.
When do I choose PUE vs PPD?
PUE — single payment — when the customer already paid when you issue, or will pay the same day. PPD — deferred/partials — when they'll pay later: credit, installments, or a future date. With PPD you'll issue a payment complement for each payment received. ContaGPT guides you through both flows.
Can I invoice without the customer's details?
Yes. If they have no RFC or won't give it, we issue to the general public using XAXX010101000. The invoice is valid for you as issuer; they can't deduct it, but you stay compliant with the SAT. Just ask us for a "general public" invoice.
Can I cancel an issued invoice?
Yes, under SAT rules. Under ~$1,000 MXN you can cancel directly. Above that, your customer must accept (they have 3 business days). If you're replacing it, we stamp the new one first, then cancel the original linked to it. We walk you through each step.
What CFDI types do you issue?
Income invoices (type I) for sales, services, fees, and rent. Payment complements (type P) for your PPD invoices. CFDI cancellations with the correct SAT motives. All version 4.0, stamped by an authorized PAC.
Do I have to send you my Constancia de Situación Fiscal?
No. With your e.firma we pull it straight from the SAT portal for you, and we pull it again every 30 days so it never goes stale. If you need it for paperwork, ask us on WhatsApp and we'll send the PDF right away.
Can you get me my Opinión de Cumplimiento (32-D)?
Yes. We generate it with your e.firma straight from the SAT portal and keep it current every 30 days. Ask for it on WhatsApp — write "opinión de cumplimiento" — and the PDF arrives right away, with the sentido (positive, negative, or not positive), the folio, and the date it was generated. You can also download it from your dashboard, and your accountant sees it from theirs.
Can my accountant see my invoices?
Yes, and you work on the same account. Your accountant sees your issued and received invoices and your taxes for the month without emailing you for XMLs. You can keep them read-only, or also authorize them to invoice on your behalf from their own WhatsApp. You choose which RFC they see, and you can revoke access anytime.
What exactly do you do with my e.firma and my CSD?
Your e.firma is used for four things and nothing else: signing the service agreement once, downloading your invoices from the SAT, fetching your Constancia de Situación Fiscal, and generating your Opinión de Cumplimiento (32-D). Your CSD is used only to stamp the CFDIs you authorize — issuing them and, if you ask, cancelling them. Both are encrypted with AES-256 and the key that opens them lives in a hardware security module (HSM); no human at ContaGPT can read them.
What happens if my CSD or e.firma is about to expire?
We warn you ahead of time. We check the expiry dates every day and message you on WhatsApp starting two months out, then again as the date gets closer. It matters because the day your CSD expires you can no longer issue invoices, and if your e.firma expires we can no longer download your invoices from the SAT. Every reminder carries the link to upload the new certificate — open it on your computer once you have the file and you keep invoicing without a gap.
How much does it cost?
We're in private beta and set pricing with you based on volume. We don't charge for questions — only for invoices issued — and there are no forced monthly fees or long-term contracts. Message us on WhatsApp and we'll shape a plan.
Are my tax details safe?
Yes. Your invoices and SAT data are stored encrypted, and your SAT credentials (e.firma and CSD) carry an extra layer of AES-256 encryption with the key held in hardware. We comply with LFPDPPP. We never share your RFC, tax data, or invoices with third parties. You can request deletion whenever you want.
Your tax data, handled the right way.
Your e.firma and CSD, encrypted with AES-256
Each file is encrypted with its own key, and that key is held in a hardware security module (HSM). No human at ContaGPT can read them.
Used only for what you authorize
The e.firma: signing your agreement once, downloading your invoices from the SAT, and fetching your Constancia and your Opinión de Cumplimiento. The CSD: stamping and cancelling your CFDIs. Nothing else.
LFPDPPP · no sharing with third parties
We comply with the Federal Law on Protection of Personal Data Held by Private Parties. We don't sell, lend, or transfer your tax data.
Your next invoice,
in one message.
Send us a WhatsApp and we'll get in touch. We're in private beta and make sure every user has a great experience from the first message.
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