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Sales & invoicing
This is where you get paid. Pick a customer, add what you sold, and MGH Books writes a clean, GST-correct invoice — the right CGST/SGST or IGST, the totals and the due date — in seconds. The same screen also makes quotations, sales orders, delivery challans and credit notes.
Read this first
- ▸ You don't calculate GST — the app applies each item's rate and the place-of-supply rule for you.
- ▸ Customer + items = invoice: pick a saved party and items, and their details, HSN and tax flow in automatically.
- ▸ One screen makes many documents — invoice, quotation, sales order, delivery challan and credit note.
- ▸ Share finished invoices instantly on WhatsApp or as a PDF, with a UPI link so customers pay on the spot.
What you can create
| Document | Use it for | Plan |
|---|---|---|
| Tax Invoice | Your standard GST sales bill | Shuruat |
| Proforma Invoice | A pre-sale estimate that looks like an invoice | Pragati |
| Quotation / Estimate | Price quotes for prospects | Pragati |
| Sales Order | Confirmed orders awaiting delivery | Pragati |
| Delivery Challan | Goods movement before/without invoicing | Pragati |
| Credit Note | Sales returns & adjustments | Pragati |
Being straight with you
- • GST follows the Place of Supply: same-state → CGST+SGST; other-state → IGST. If a tax looks wrong, check the place of supply first.
- • Invoice numbers auto-increment, but you can set the series — keep them sequential for GST.
- • e-Invoice (IRN) and e-Way Bill use the government systems, need your own eligibility/credentials, and are Unnati+. MGH prepares them; the portal issues them.
- • POS and the advanced document types above need Pragati or higher.
Step by step
- 1
Open a new invoice
Sales → New InvoiceStart a Tax Invoice. The number and date fill in automatically; a due date is set from the payment terms.
- 2
Pick the customer
Select a party — GSTIN, address, state and place of supply auto-fill. You can add a new customer on the fly.
- 3
Add items
Add each line: name, HSN, rate and GST come from the item record. Set quantity and any per-line discount.
- 4
Review tax & totals
The summary shows taxable value, CGST+SGST or IGST, optional round-off, and the grand total. Add notes or terms if needed.
- 5
Record payment & save
Optionally record an advance or full amount received, then Save & Share via WhatsApp or PDF with a UPI link.
Before you start: three things that make billing fast
Billing in MGH Books is quickest when a little setup is done once. Spend five minutes on these and every future invoice takes seconds.
- Save your items with their price, HSN code and GST rate — so they fill in automatically on every bill.
- Save your regular customers (parties) with their GSTIN and state — so the right GST is applied without you thinking about it.
- Add your UPI ID in Settings — so a pay-now QR/link appears on every invoice and customers pay on the spot.
A tour of the invoice screen
The invoice screen looks busy the first time, but it's just five parts. Once you know them, you'll never look for a field again.
- Header — invoice number (auto), date and due date (set from payment terms).
- Customer — the party you're billing; their GSTIN, address, state and place of supply auto-fill.
- Line items — each product or service: name, HSN, quantity, rate, and any per-line discount.
- Tax summary — taxable value, CGST+SGST or IGST, optional round-off, and the grand total.
- Footer — notes, terms and the Save & Share options (WhatsApp, PDF, print).
How GST is worked out on your bill (with an example)
You never calculate GST yourself — but it helps to understand what the app is doing, because it explains why a tax sometimes looks different from what you expected.
GST follows the Place of Supply. If your customer is in the same state as you, the GST splits into CGST + SGST. If they're in a different state, it becomes a single IGST. The total tax is the same either way; only the split changes.
| Sale of ₹10,000 @ 18% GST | Same state (Maharashtra → Maharashtra) | Other state (Maharashtra → Gujarat) |
|---|---|---|
| Taxable value | ₹10,000 | ₹10,000 |
| CGST (9%) | ₹900 | — |
| SGST (9%) | ₹900 | — |
| IGST (18%) | — | ₹1,800 |
| Invoice total | ₹11,800 | ₹11,800 |
B2B or B2C — which one are you raising?
Every sale is either B2B or B2C, and MGH Books handles both. The only practical difference for you is whether you add the customer's GSTIN.
| B2B | B2C | |
|---|---|---|
| Who | Another GST-registered business | An end customer |
| GSTIN needed? | Yes — so they can claim ITC | No |
| Shows in their GSTR-2B? | Yes | No |
| Typical use | Wholesale, services to firms | Retail counter, walk-in sales |
One screen, many documents
The same billing screen creates more than tax invoices. Use the right document for the moment and everything stays connected — a quotation can become an invoice in a click, with no re-typing.
| Document | Use it when | Plan |
|---|---|---|
| Tax Invoice | You've made a sale and want payment | Shuruat |
| Quotation / Estimate | A prospect asks for a price | Pragati |
| Proforma Invoice | You need a pre-sale bill (e.g. for advance) | Pragati |
| Sales Order | An order is confirmed but not yet delivered | Pragati |
| Delivery Challan | Goods move before/without an invoice | Pragati |
| Credit Note | A customer returns goods or you adjust a bill | Pragati |
Sharing the invoice and getting paid faster
A saved invoice is only useful once it reaches the customer. MGH Books makes the last step the easiest one.
- Share on WhatsApp in one tap — the customer gets a clean PDF and a UPI pay link.
- Send as a PDF by email, or print on A4/A5 or an 80mm thermal roll (POS).
- Record the payment (full or advance) right on the invoice; the balance and your books update instantly.
Editing, cancelling and handling returns
Mistakes happen. Here's the clean way to fix each one so your GST stays correct.
- Need to fix a typo? Edit the invoice — you can change it freely until it's locked into a filed GST return.
- Customer returned goods, or you over-charged? Raise a Credit Note against the original invoice — this is the GST-correct way to reduce a sale.
- Raised an invoice entirely by mistake? Cancel it before filing; after filing, use a credit note. Either way, keep the trail.
e-Invoice (IRN) and e-Way bill — when they apply
These two use the government's own systems. MGH Books prepares them with your invoice data so you don't re-type, but the portal actually issues them, and they need your own eligibility and credentials.
- e-Invoice (IRN): required once your turnover crosses the notified threshold. The IRN and a signed QR attach to your invoice.
- e-Way bill: generally needed to move goods above ₹50,000 in value (rules vary by state and goods).
- Both features are on the Unnati plan and above.
Recurring & subscription invoices
If you bill the same customer the same amount every month — a retainer, a maintenance contract, a subscription — set it up once and let it run.
From the Pragati plan, create a recurring invoice with a cycle (monthly, quarterly) and MGH Books raises it automatically each period, so you never forget to bill.
Good habits for clean GST
- Keep invoice numbers sequential and unbroken — it's a GST requirement and avoids notices.
- Always confirm the customer's state so the right CGST/SGST vs IGST applies.
- Fill HSN codes on items so your GSTR-1 HSN summary is correct.
- Enter invoices promptly — the same day where possible — so your returns and reports are always current.
- Use credit notes for returns rather than editing old, filed invoices.
Troubleshooting
The GST amount looks wrong
Fix: Open the item and check its GST rate, then confirm the customer's state — inter-state sales use IGST, same-state use CGST+SGST.
The customer's GSTIN won't accept
Fix: GSTINs are exactly 15 characters. Re-check for spaces, a missing digit, or a lowercase letter.
The invoice total seems off
Fix: Check for a per-line discount, the round-off setting, and that each item's rate is correct. Tap the tax summary to see the breakdown.
The Save button does nothing
Fix: A required field is empty — usually the customer or an item amount. The field is highlighted; fill it and save.
My invoice number is out of sequence
Fix: Avoid deleting invoices. If a gap appears, set the next number in the series settings and keep it sequential going forward.
I can't edit a past invoice
Fix: It's likely locked into a filed GST return. Raise a credit note against it instead of editing.
Words you’ll see (in plain English)
- Place of Supply
- The customer's location that decides whether GST is CGST+SGST (same state) or IGST (other state).
- HSN code
- A standard code for a product that sets its GST rate and appears in your GSTR-1 summary.
- B2B / B2C
- B2B is a sale to a GST-registered business (needs their GSTIN); B2C is to an end customer.
- CGST / SGST / IGST
- The three GST components — CGST and SGST for same-state sales, IGST for inter-state.
- Proforma invoice
- A pre-sale bill that looks like an invoice, often used to request an advance.
- Credit note
- A document that reduces a sale — used for returns or corrections, the GST-correct alternative to deleting an invoice.
- IRN
- Invoice Reference Number — the unique ID a government-registered e-invoice receives.
- e-Way bill
- A document required to transport goods above a value threshold.
Ready to try it?
Create an invoice