Connect Your CRM to Electronic Invoicing: ARCA, SII and SUNAT

The deal closes over WhatsApp at 11:00 and the invoice goes out at 16:40, after someone in admin re-typed the tax ID, the VAT condition, and the line items the rep had already entered somewhere else. Connecting your CRM to electronic invoicing means linking your commercial system to the tax authority's web services — ARCA (formerly AFIP) in Argentina, SII in Chile, SUNAT in Peru, DIAN in Colombia — so that a won opportunity generates the invoice in one click, with no data re-entry. It's the integration with the best immediate return we implement, and the one no global SaaS CRM handles well in LATAM.

The real problem: double entry and its errors

In the typical un-integrated operation, every sale is entered twice (sometimes three times): in the rep's CRM or spreadsheet, in the invoicing system, and — if there's a warehouse — in the stock system. Every re-entry is a chance to make a mistake, and tax mistakes aren't free:

• Mistyped tax ID or VAT condition → a rejected invoice or, worse, one issued incorrectly that needs a credit note later.
• Differences between quote and invoice → the customer agreed on a price by chat and the invoice arrived with a different one. Argument, payment delay, friction.
• Closed deals nobody invoiced → in high-volume companies, they slip through. A distributor we work with discovered, after integrating, uninvoiced sales worth the equivalent of 2% of monthly revenue: it wasn't fraud, it was paperwork lost between two systems.
• Pure admin hours: 10-15 minutes per transaction which, at 200 transactions a month, add up to 30-50 hours of duplicate data entry monthly.

What exactly gets automated: the full circuit

A well-designed integration isn't just "issue the invoice." The closed-deal circuit has four automatable stations:

Station	What the system does	What a person stops doing
Invoice	Pulls client, line items and terms from the won opportunity, requests the CAE from ARCA, and issues	Re-keying data into the invoicing tool
Delivery	Generates the linked delivery note and deducts stock	Building the delivery note by hand and notifying the warehouse
Collections	Sends the invoice by email/WhatsApp and schedules reminders based on the due date	Chasing payments from memory
Reconciliation	Matches incoming payments (bank statement, payment gateway) against invoices and flags the settled ones	Ticking off payments in a spreadsheet

The rep clicks "Won" and everything else runs on its own, with the exceptions (clients with debt, discounts outside policy) routed for human approval. One detail that makes the difference in practice: upfront validation of tax data. The system queries the registry when the client is created — in Argentina, the registration certificate via ARCA's web service — so an invalid tax ID or VAT condition is caught at the start of the commercial relationship, not on invoicing day. This chaining is the same principle we apply in any AI automation project: the machine handles the repetitive, the person decides what matters. And if the sales channel is WhatsApp, the circuit plugs straight into the flow we describe in CRM with WhatsApp for sales.

The APIs country by country: what exists and what it costs

Good news: the region's tax authorities expose official interfaces, and they're generally free. What you pay for is the development (and, in some countries, an authorized intermediary).

Argentina — ARCA (formerly AFIP)

• WSFEv1: the electronic invoicing web service for local operations (A, B, C, credit/debit notes). Returns the CAE in seconds.
• WSFEX for exports and WSBFE for capital goods.
• Requirements: the taxpayer's digital certificate and a point of sale enabled for web services. The service is free; authentication (WSAA, with tickets that expire every 12 hours) is the technical detail that trips up most people doing it for the first time.

Chile — SII

• A DTE (Electronic Tax Documents) model with a digital signature and submission to the SII. More demanding on initial certification than ARCA: there's an issuer homologation process.
• Practical alternative: invoice via an authorized provider with an API (several charge per document or a monthly subscription) and have the CRM integrate against that provider.

Peru — SUNAT

• CPE (Electronic Payment Documents) in UBL format. Issuance can be direct against SUNAT or through an OSE (Electronic Services Operator), which is the norm at volume: it validates and forwards on your behalf, at costs on the order of cents of a dollar per document.

Colombia — DIAN

• Electronic invoicing with upfront validation: the document is validated with the DIAN before being delivered to the customer. You operate with your own enabled software or via an authorized technology provider with an API, which charges per document or package.

In all four countries the pattern is the same: the interface exists, it's stable, and it's documented — what's missing is your CRM speaking to it. No global SaaS ships it out of the box.

How many hours a month does your admin team lose re-entering sales that were already entered? Book an intro call and we'll show you the deal→invoice circuit working.

Why this is the standout argument for a custom CRM

Try searching "ARCA" or "SUNAT" in the Salesforce or HubSpot marketplace. What you'll find are third-party connectors: with their own monthly fee, support in English or nonexistent, and field mapping designed for something else. When ARCA changes a regulation (and it does), you're left waiting for a third party to update its connector.

A custom CRM flips the logic: your country's invoicing isn't an add-on, it's part of the design. Your price lists, your VAT conditions, your discount-approval circuit, and your electronic document series all live in the same system. And if you also need stock, purchasing and warehouse, the natural next step is a custom management system where the CRM is just one more module. We compare both worlds in depth in Custom CRM vs Salesforce.

Realistic development costs (LATAM, 2026):

• Basic issuance against ARCA/SII/SUNAT/DIAN from the won opportunity: USD 2,000 – 4,000.
• Full circuit (invoice + delivery note + collections + reconciliation): USD 5,000 – 12,000.
• Timeline: 3 to 8 weeks depending on scope. The typical return, counting only recovered admin hours and sales that used to go uninvoiced, lands between 4 and 10 months.

When NOT to integrate (yet)

For the recommendation to mean anything, here's the flip side too:

• Fewer than ~50 invoices a month: manual entry costs you few hours; the development doesn't pay back quickly. ARCA's web invoicer or your accounting system are enough.
• The sales process still lives in spreadsheets: bolting invoicing onto a CRM nobody uses is building the roof before the walls. Sort out the base first — start by moving from Excel to a CRM.
• Your ERP already invoices well and the bottleneck is elsewhere: sometimes what's missing isn't issuance but collections or reconciliation; integrate that specific piece and don't rebuild what works.
• You operate in several countries with minimal volume in some: integrate first the country that concentrates your invoicing; the rest can wait for their own ROI.

From closed deal to invoice, for real

The acid test of any commercial system is what happens in the five minutes after "Won." If the answer involves someone re-typing a tax ID, there's immediate room to improve.

At Deepyze we've been integrating electronic invoicing with commercial systems for companies in Argentina and across the region — you can see examples in our projects — and the circuit always closes the same way: a fixed price agreed before a single line of code is written, a concrete proposal in 24 hours, and a development team in your own time zone that knows what a CAE is without you having to explain it. Tell us how you invoice today and we'll send you back the plan so your next closed deal invoices itself.