Kolleno Payments
Issuing an e-invoice is now a requirement for many businesses. But it doesn’t have to be a time-consuming process to switch to. Whether you are uploading to an e-invoice portal or using automated tools, this article explains what to include, where to submit it, and how to stay compliant with tools like Kolleno.
What Is an E-Invoice?
An e-invoice is a structured invoice issued in electronic format and submitted through an authorized e-invoice portal. Unlike a traditional invoice, it isn’t created manually or emailed as a PDF. Instead, it’s generated in a standard format (often as a JSON file) and uploaded directly to an invoice registration portal (IRP) for validation.
The goal is simple: reduce errors, strengthen compliance, and make it easier for businesses to track and manage invoice data. Once validated, the invoice receives a unique invoice reference number (IRN) and a government-approved QR code. These confirm the document is a valid e-invoice—ready to be shared with clients, stored for audit, or integrated into your accounting systems.
Many businesses are now required to use electronic invoices based on their annual turnover and status under the GST system. If you’re unsure whether you fall under this mandate, check the latest guidelines on your local GST portal or GSTN portal.
Step-by-Step: How To Generate an E-Invoice Online
Generating an e-invoice is straightforward once you understand the flow. You can do it manually via a government e-invoice portal, or use e-invoicing software like Kolleno to handle the steps for you. Here’s how the process works.
1. Choose a method
You can either upload a JSON file to the government’s invoice registration portal, or use an e-invoicing solution that integrates with the IRP and automates the submission. Kolleno, for example, handles this behind the scenes—removing the need to manage files or log into government portals.
2. Create your invoice
Enter all required invoice data, including:
- A unique invoice number
- Date of issue
- Buyer and seller contact details
- List of services provided or goods sold
- Total amount, credit notes (if applicable), and payment instructions
- Your company name, registered address, and logo
- Applicable tax details if you’re under the GST system
You can use a professional invoice layout or a free invoice template, but the key is to ensure all fields are present and accurate.
3. Assign an Invoice Reference Number (IRN)
If using the IRP manually, this is generated during the upload process. If using a tool like Kolleno, the invoice reference number is issued automatically after submission.
4. Upload to the IRP or submit via software
If doing it manually, convert the invoice into a JSON file and upload it to the official e-invoice portal. If using Kolleno or similar e-invoicing software, the file is created and sent automatically.
5. Receive validation
Once accepted, the portal returns a QR code, timestamp, and the final IRN. This confirms the document is a valid e-invoice.
You can now send the e-invoice to your buyer, save it for audit, and integrate it into your accounts or ERP system.
Why Use E-Invoicing Software Like Kolleno?
Creating a valid e-invoice manually—filling in fields, generating a JSON file, uploading to the invoice portal, and tracking status—takes time and leaves room for errors. E-invoicing software like Kolleno removes that complexity.
Kolleno automates the invoicing process from start to finish. It lets you create professional invoices using pre-set templates, populate fields with saved client and account details, and submit the final document directly to the invoice registration portal. There’s no need to log in separately, format files, or worry about rejections due to missing data.
Once submitted, Kolleno pulls back the approved invoice reference number, QR code, and timestamp automatically. This means your invoice is stored in the system and linked to your accounts without extra admin.
Kolleno also boasts a range of additional features to facilitate the e-invoicing process:
- Auto-generation of credit notes and follow-up reminders
- Centralized dashboard to track status across all clients and documents
- Built-in payment tracking and reconciliation tools
- Sync with your accounting or ERP platform for cleaner financial data
For businesses issuing e-invoices at scale, Kolleno helps save time, reduce risk, and ensure every single invoice meets compliance standards.
Common Mistakes To Avoid When Generating an E-Invoice
Even with the right tools, mistakes during the e-invoicing process can lead to delays, rejections, or incorrect filings. Here’s what to watch out for.
Missing or incorrect invoice data
Leaving out fields like the invoice number, buyer contact details, or payment instructions can result in an invalid submission. Always check that all the details are complete before uploading or sending.
Improper invoice format
If you’re submitting through an invoice registration portal, the invoice must be in a structured JSON file. PDFs or manually created invoices aren’t accepted unless your e-invoicing software converts them correctly.
Duplicate invoice numbers
Reusing the same invoice number for multiple clients or services can trigger errors at the IRP. Every invoice must have a unique ID for the current financial year.
Incorrect handling of credit notes
Failing to generate or link credit notes properly may cause mismatches between your reported sales and actual billing records. Use software that tracks and reconciles these documents automatically.
Manual uploads without validation
Uploading to the e-invoice portal without confirming that the file is valid—especially if created manually—can result in rejections. Use tools that validate invoice data before submission.
Final Thoughts
Generating a valid e-invoice doesn’t need to be slow or complicated. If you choose the right e-invoicing solution, you can eliminate manual uploads, reduce errors, and stay compliant—without adding to your admin load. Whether you’re issuing a single bill or managing hundreds each month, automation is no longer a nice-to-have. It’s essential.
Kolleno gives you everything you need to manage the full invoicing process—from creation to submission and beyond. It’s faster, more accurate, and built for growing teams.Ready to simplify e-invoicing? Book a demo with Kolleno and see how it works.
