Issuing Electronic Invoices for E-Commerce: A Step-by-Step Guide for Beginners
Mariana Lopes · 2026-10-07
REGISTERING WITH THE STATE TREASURY DEPARTMENT AND OBTAINING A DIGITAL CERTIFICATE
- Registering with the State Treasury Department (SEF): Visit your state’s SEF website and register as a taxpayer. This may involve filling out forms and submitting documents such as your CNPJ, articles of incorporation, and the partners’ personal documents.
- Obtaining a Digital Certificate: After registering, hire an authorized company to issue your digital certificate (type A1 or A3). Type A1 is a file that can be installed on your computer, while A3 is a physical token. The cost can range from R$ 100 to R$ 600 per year, depending on the type and the company you choose.
HOW TO GENERATE AN INVOICE IN YOUR E-COMMERCE PLATFORM’S SYSTEM
- Platform Integration: Check whether your e-commerce platform (such as Shopify, WooCommerce, or Magento) has a built-in feature or plugins for issuing invoices.
- System Setup: Enter your business details, such as your CNPJ, state registration, and digital certificate.
- Issuing the Invoice: When completing a sale, select the option to issue an invoice. The system will automatically generate the NF-e, which can be sent directly to the SEF.
Tips for proper product categorization
- Tax Classification: Use the Mercosur Common Nomenclature (NCM) to categorize your products correctly. Choosing the wrong classification can result in fines and issues when issuing an invoice.
- NCM Lookup: Use online tools or consult the Federal Revenue Service table to find the correct NCM. Some e-commerce platforms already offer support for this.
Invoice delivery deadlines and legal requirements
- Issuance Deadline: The invoice must be issued within 24 hours of the sale. For sales that include delivery, the invoice must accompany the goods.
- Legal Requirements: Keep all issued invoices for at least five years, as required by tax law.
How to correct and cancel incorrectly issued invoices
- Correcting Invoices: To correct an invoice, issue an Adjustment Invoice (Correction Letter) if the error is not serious (details such as the address or business name). Otherwise, you need to cancel the previous invoice and issue a new one.
- Cancellation: The invoice must be canceled within 24 hours of issuance. To do this, access the SEF system and follow the indicated procedure.
This process must be followed carefully to avoid legal complications and ensure your e-commerce business stays tax-compliant.
How many invoices have you issued in the last month?