Quick answer
Common mistakes include missing invoice numbers or dates, unclear service descriptions, incorrect GST calculations, missing payment terms, and sending invoices without clear payment instructions.
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Payment terms, reminders, overdue invoices and practical collection workflows.
Each of these mistakes has delayed payment for someone. Check how many you're making — and fix them today.
InvoicePilot prevents all 10 of these mistakes
Auto-fills GSTIN, SAC code, due date, tax split. Free forever.
No due date
HighThe mistake
Sending an invoice with "payment due on receipt" or no date at all.
The fix
Always write a specific date: "Due: March 23, 2026". Vague terms = indefinite delays. Net 14 is a good default.
Wrong GST breakup (CGST/SGST vs IGST)
CriticalThe mistake
Using CGST+SGST for a client in a different state, or IGST for a same-state client.
The fix
Same state = CGST 9% + SGST 9%. Different state = IGST 18%. Wrong split = accounts team rejects the invoice.
Missing GSTIN
CriticalThe mistake
Not including your GSTIN or the client's GSTIN on the invoice.
The fix
GST-registered clients cannot claim ITC without both GSTINs on the invoice. They will ask you to re-issue it.
No invoice number
HighThe mistake
Using random or repeated invoice numbers — or no number at all.
The fix
Use a sequential format: INV-2026-001, INV-2026-002. Required by GST law. Helps with tracking and disputes.
Sending to the wrong person
HighThe mistake
Sending the invoice to the project manager instead of the accounts/finance team.
The fix
Ask on day one: "Who should I address invoices to?" Then send to finance directly, CC the project contact.
Sending the invoice late
HighThe mistake
Waiting days or weeks after delivery to send the invoice.
The fix
Send within hours of delivery. The longer you wait, the less urgency the client feels. Same-day invoicing gets paid fastest.
No SAC code
MediumThe mistake
Missing the SAC (Service Accounting Code) on the invoice.
The fix
Required for GST-registered freelancers. Common codes: 998314 (IT/web development), 998392 (design), 998312 (consulting).
Vague service description
MediumThe mistake
"Design work" or "consulting" with no detail.
The fix
Be specific: "Brand identity design — logo, colour palette, typography guide, 2 rounds of revisions". Specific descriptions reduce disputes.
No bank details or payment options
HighThe mistake
Just sending a PDF with no info on how to pay.
The fix
Include: bank name, account number, IFSC code, and UPI ID. The easier you make payment, the faster it happens.
No follow-up
HighThe mistake
Sending the invoice and waiting in silence.
The fix
Set a reminder: follow up 2 days before due date, on due date, 7 days after. Most late payments are just forgotten — a nudge fixes it.
Not specifying a clear due date. Terms like "payment due on receipt" are ambiguous and give clients no concrete deadline to work against — a specific date like "Due: March 23, 2026" removes that ambiguity entirely.
A wrong CGST/SGST vs. IGST split is one of the most common reasons a client’s accounts team rejects or delays an invoice, since it affects their ability to claim input tax credit correctly. Same-state clients need CGST+SGST; different-state clients need IGST.
Yes — if your invoice is missing your GSTIN (or your client’s, if they’re registered), many corporate accounts teams will bounce the invoice back for correction before processing payment, adding days or weeks of delay.
InvoicePilot auto-fills GSTIN, SAC codes, GST split, due dates and bank details. Free forever.
Start Free — No Credit Card →How to Create a Professional Invoice in India (Free Template)
Step-by-step guide to creating invoices that get paid faster. Includes free template.
GST Invoice Format for Freelancers in India (2026) — Complete Guide
Mandatory fields, SAC codes, CGST/SGST vs IGST, export invoices under LUT — everything you need.
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