ARCA electronic invoicing integration: what changed in 2026 and what to check before December 1

Starting December 1, 2026, ARCA (Argentina's tax agency, formerly AFIP) rejects authorization for any electronic invoice that doesn't report the customer's VAT status in the web service request. The data has to travel inside the CAE request: having it on the customer record or printed on the PDF isn't enough. If your ERP invoices through a connection to ARCA, you need to confirm it already sends that field. And if you still issue invoices in one place and record them in another, now is a good time to integrate the two for good.

Renaming AFIP as ARCA didn't change electronic invoicing: your tax ID (CUIT), your tax password and the web services all work the same. What did change in 2026 is a set of rules that directly affect the systems that issue invoices. This article lays them out and explains what a company invoicing from its management system in Argentina needs to check, including subsidiaries of foreign companies, or companies still doing that work twice by hand.

What changed with ARCA, and what didn't?

In October 2024, Argentina's government dissolved AFIP and created the Customs Collection and Control Agency (ARCA) as its legal successor. For anyone issuing invoices, the change was a new name and a new portal: tax IDs, tax passwords, points of sale, digital certificates and the e-invoicing web services all stayed the same. A system already invoicing through AFIP didn't need any changes because of the rename.

The real work comes from the resolutions ARCA has issued since then, especially in 2026.

The 2026 changes that affect your system

The VAT status rule is the most urgent, because it stops invoicing outright: if the system doesn't send the field, ARCA doesn't return a CAE, and the invoice doesn't exist. Developers know it as error 10242, which flags the field as missing or invalid.

The underlying problem: invoicing in one place, recording in another

In many SMBs, invoicing and recording are separate tasks: first the invoice is issued in ARCA's online invoicing tool or a standalone program, and then someone enters it into the ERP (or a spreadsheet) so inventory and the customer's account are updated. One piece of data, entered twice.

With few invoices, it's manageable. As volume grows, so do the wasted hours and the risk of mismatches. And every new rule, like the VAT status requirement, has to be handled twice: once in the invoicing tool and again in the ERP.

Signs your company is still doing the work twice

• Someone enters into the ERP every invoice already issued in ARCA's invoicing tool.
• Invoiced and recorded amounts haven't matched at least once.
• Closing the day's sales means cross-checking two sources.
• Inventory doesn't update when you invoice, only when someone enters the invoice.
• Nobody is sure every customer's VAT status is on file and correct.

If two or three of these sound familiar, you're already paying for unintegrated invoicing, in time and in risk of errors.

What integrating e-invoicing means (and what it doesn't)

Integration doesn't change how the company invoices before ARCA or settle any tax question: ARCA still validates and authorizes every invoice. What changes is who does the work. Instead of one person issuing in one place and entering in another, the ERP builds the invoice with the customer's data, sends it through the web service, receives the CAE and, in the same step, updates inventory, the customer's account and the sales reports.

The number in your system is always the one ARCA validated, because it's the same process, not a copy. And when a rule changes, you adapt it in one place.

If you invoice with Odoo

Odoo has an Argentine localization with electronic invoicing connected to ARCA's web services: standard electronic invoices (wsfev1), export invoices (wsfexv1) and fiscal bonds (wsbfev1). In Odoo Enterprise, it comes in the official Argentine e-invoicing module; in Community, it takes additional modules. Either way, you need the company's digital certificate, and it's best to test first in the homologation (testing) environment, which is separate from production.

If your Odoo has custom development around invoicing, check that it doesn't build the web service request on its own and skip the new field. That's where most failures show up.

What to check before December 1

1. List everything that issues invoices: the ERP, the online store, the point of sale, any standalone invoicing tool.
2. Ask each vendor, in writing, whether their system already sends the customer's VAT status in the CAE request, and from which version.
3. Clean up your customer data: every customer needs a correct VAT status on file, end consumers included.
4. Test in homologation: issue test documents of each type (invoice, credit note, debit note) for customers of each VAT status.
5. Prepare the contingency plan: since August, CAEA is only for connection failures. Decide who switches to it and how those invoices get reported afterward.
6. Confirm the specifics of your business with your accountant. This article covers the systems side; it isn't tax advice.

How we help

We connect management systems to ARCA's web services, in Odoo or in custom software: the system builds the invoice, requests the CAE and updates the rest of the operation in a single step. We also review existing integrations to adapt them to the new rules, and keep them current through support and maintenance.

If you're not sure where your invoicing stands, start with a technology assessment: in one meeting, we'll tell you which systems need adapting and where to begin.

Further reading

• Automating invoicing: from purchase order to payment without manual work.
• How to integrate two systems that don't talk to each other.
• If you also invoice in Spain: Verifactu in Odoo: what changes, the 2027 deadlines and how to prepare.