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# How to Make HSN/SAC Mandatory for GST Invoices?

When creating GST invoices, adding the correct **HSN/SAC code** for every line item is essential, especially for **e-invoices**, where missing HSN/SAC details can cause errors during e-invoice generation.

With Refrens, you can enable **Compulsory HSN/SAC** for your business and make sure this important detail is never missed.

Once enabled, system will require an **HSN/SAC code for every line item** on your GST invoices before you can proceed. This helps you avoid last-minute errors and ensures your invoices are ready for e-invoice generation.

# How to Enable Compulsory HSN/SAC

###### 1. Go to Business Settings:

In your Refrens account, go to: **Business Settings → Accounting → GST Configuration**

![](https://storage.crisp.chat/users/helpdesk/website/-/a/b/8/8/ab884d8153100800/image_9flzf9.png =855xauto)


###### 2. Look for the Compulsory HSN/SAC option.

The setting is turned **OFF by default**, so your existing invoice workflow remains unchanged unless you choose to enable it.

![](https://storage.crisp.chat/users/helpdesk/website/-/a/b/8/8/ab884d8153100800/toggle-on_hu4zpk.gif =783xauto)

Turn ON the **Compulsory HSN/SAC** toggle.

When enabled, HSN/SAC will be required for every line item in GST documents.

|| Note: This setting applies when GST is configured on the invoice. Non-GST invoices are not affected.

# How It Works While Creating an Invoice

###### 1. Configure GST on Your Invoice:

While creating an invoice, click **Configure GST** and select the required GST configuration.

Once GST is configured and **Compulsory HSN/SAC** is enabled for your business, the HSN/SAC field becomes mandatory for each line item.

![](https://storage.crisp.chat/users/helpdesk/website/-/a/b/8/8/ab884d8153100800/image_xvm772.png =867xauto)

###### 2. Add HSN/SAC for Each Line Item

Enter the appropriate HSN/SAC code in the **HSN/SAC** field for every item on the invoice.

If an HSN/SAC code is missing, Refrens highlights the field and displays: **“HSN/SAC is required”**

This helps you identify the missing information before proceeding.

![](https://storage.crisp.chat/users/helpdesk/website/-/a/b/8/8/ab884d8153100800/image_1kvzyka.png =781xauto)


If your invoice contains multiple line items, make sure an HSN/SAC code is entered for **each applicable item**.

If any line item is missing HSN/SAC, Refrens displays a validation message listing the missing details.

![](https://storage.crisp.chat/users/helpdesk/website/-/a/b/8/8/ab884d8153100800/image_p25rhq.png =759xauto)


# Why Should You Enable Compulsory HSN/SAC?

Enabling this setting can help you:
* Avoid issues when using GST-related reporting and e-invoicing features.
* Reduce compliance-related errors.
* Maintain more consistent invoice data across your business.

# Frequently Asked Questions

**1. Does this apply to all invoices?**
No. The requirement applies when **GST is configured on the invoice** and Compulsory HSN/SAC is enabled for your business.

**2. Can I turn the setting off later?**
Yes. You can return to **Business Settings → Accounting → GST Configuration** and turn off **Compulsory HSN/SAC**.

**3. What Happens When Compulsory HSN/SAC Is Turned Off?**
If the Compulsory HSN/SAC setting is OFF, the HSN/SAC field remains optional, as it was previously. This gives you flexibility when preparing invoices where the HSN/SAC classification is not yet available.

**4. Does this change my existing invoice workflow if I don't enable it?**
No. The setting is optional and defaults to OFF. If you leave it disabled, HSN/SAC continues to behave as before.

In case you need further assistance, reach out to us on live chat support or drop an email at [__care@refrens.com__](mailto:care@refrens.com).