Invoice Maker
Create professional GST and sales tax invoices instantly online. Generate beautiful printable PDF invoices for free.
What Each Field on This Form Is Actually For
A professional invoice isn't just a bill with a total at the bottom — it's a legal and accounting record, and certain fields exist specifically to satisfy tax and audit requirements, not just to look complete.
NTN (National Tax Number) fields identify the registered taxpayer on both sides of the transaction. Including both the seller's and buyer's NTN is what allows a sales tax invoice to be used as supporting documentation for tax filing and input tax credit claims — an invoice without this is generally treated as an informal bill rather than a tax-compliant document in jurisdictions that use NTN-style registration.
Invoice number and reference number serve different purposes: the invoice number is your own sequential record for bookkeeping (and should never repeat — reusing an invoice number is a common audit red flag), while a reference number typically ties the invoice back to a purchase order or quotation the client already has on file, making it easier for them to match your invoice against their own records.
DC No (Delivery Challan number) links the invoice to the physical goods delivery note, if one was issued separately before billing — common in wholesale and B2B transactions where goods are delivered first and invoiced afterward. If you invoice and deliver simultaneously, this field can be left blank.
Per-item tax rate, not one flat invoice-wide rate: this form lets you set a different tax percentage per line item rather than one rate for the whole invoice, because in most GST/VAT systems, different goods and services legitimately carry different tax rates on the same bill — a mixed invoice with both an 18%-rated service and a 0%-rated exempt item is common and needs to be itemized correctly rather than averaged.
Mistakes That Cause Invoices to Get Rejected or Disputed
Vague item descriptions
"Consulting services" or "Miscellaneous" invites disputes and slows down client approval. Describing exactly what was delivered — dates, scope, or a reference to a signed agreement — makes an invoice far harder to question or delay payment on.
Missing or duplicate invoice numbers
Reusing an invoice number (even for a different client) breaks sequential audit trails and can flag an entire set of records for review. Keep one running sequence across all invoices, not a separate sequence per client.
Tax calculated on the wrong base amount
If a discount is applied, tax should generally be calculated on the post-discount amount, not the original price — calculating tax before discount overcharges the client and creates a mismatch with their own accounting records.
No clear payment terms
"Payment due" without a specific date or number of days (e.g. "due within 15 days of invoice date") is one of the most common reasons payments get delayed indefinitely — an ambiguous term gives the client no concrete deadline to work against.
How to Use the Invoice Maker
Enter Business Details
Add your company name, logo, contact details, and billing information.
Add Client Information
Enter customer details including name, address, and invoice information.
Add Invoice Items
Add products, services, quantities, prices, and per-item tax rates.
Generate & Download
Instantly create and download your professional PDF invoice online.
Frequently Asked Questions
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