---
url: /gst-manager-acellemail/guides/configure-gst.md
description: >-
  Walk through Setup → Company & Tax to enter your GSTIN, home state, default
  rate, tax label, SAC/Purpose codes and invoice numbering so every AcelleMail
  invoice is GST-compliant.
---

# Configure GST

This walkthrough gets GST Manager producing correct tax invoices. You'll fill in
**GST Manager → Setup → Company & Tax** — your company identity, GSTIN, home state, default rate,
codes and invoice numbering. Have your **GSTIN** (your 15-character GST registration number) and
**PAN** handy before you start.

![The Company & Tax setup screen](/gst-manager-acellemail/img/gst-configure-gst-company-tax.png)
*GST Manager → Setup → Company & Tax*

::: info Why this matters
Your home state and GSTIN drive the whole tax engine: whether an invoice splits into **CGST + SGST**
(a sale inside your state) or a single **IGST** line (a sale to another state), and whether a
customer is treated as **B2B** (they have a GSTIN) or **B2C** (they don't).
:::

## Step 1 — Company info

In the **Company info** section, enter your **Company name** and **Company GSTIN**. These identity
fields are **shared with your AcelleMail admin contact** — editing them here updates the admin
contact too, so you only maintain them in one place. Type your GSTIN carefully; it prints on every
tax invoice. To confirm the format is right, see
[GSTIN validation](/gst-manager-acellemail/guides/gstin-validation).

## Step 2 — Address and home state

Fill in **Address line 1/2**, **City**, **ZIP / PIN** and **Country**, then set **State**. The
State field is the one that matters most for tax: its help reads *"Used to decide CGST+SGST vs IGST.
Matched against the Indian states registry."* Pick your registered home state from the list so the
engine can compare it against each customer's state.

## Step 3 — Tax & GST

Under **Tax & GST**, set your **Default GST rate** (for example, 18). Then set the **Tax label** —
its help reads *"Shown as the label of the consolidated tax line on PDFs (e.g. GST)."* Most sellers
leave this as **GST**.

## Step 4 — SAC & Purpose code

Enter your **SAC code** (the service accounting code that classifies your service for tax) and your
**Purpose code** (the RBI code that classifies export payments). Both are *"Applied to every line
item on every invoice,"* so set them once here. How these appear per invoice is covered in
[GST classification](/gst-manager-acellemail/features/gst-classification).

## Step 5 — Invoice numbering

In **Invoice numbering**, set the **Invoice number format** and the **Next invoice number**. The
format uses a sprintf template — for example `%08d` produces `00000001`, `%d` gives a plain number,
and `INV-%06d` gives `INV-000001`.

::: tip These two are core settings
The invoice number format and next number are **AcelleMail core settings**, shared with your general
settings — changing them here changes them everywhere. Set the next number to continue your existing
sequence rather than reset it.
:::

## Step 6 — Save changes

Click **Save changes**. You'll see the confirmation **"Settings saved."** Your invoices now carry
your GSTIN, correct tax split and numbering. Continue with your invoice logo, footer and bank
details in [Invoice identity and bank details](/gst-manager-acellemail/guides/invoice-identity-and-bank).

## Related pages

* [GSTIN validation](/gst-manager-acellemail/guides/gstin-validation)
* [Invoice identity and bank details](/gst-manager-acellemail/guides/invoice-identity-and-bank)
* [GST classification](/gst-manager-acellemail/features/gst-classification)
* [Settings reference](/gst-manager-acellemail/settings)