GST Billing Software — Invoice, Track & Recover Dues on WhatsApp
Generate GST-compliant invoices, track every client's outstanding, send automated WhatsApp payment reminders, and recover overdue dues — purpose-built for Indian businesses.
FastFee is a GST billing software for Indian businesses that goes beyond invoicing. It tracks party-wise outstanding, sends automated WhatsApp payment reminders on overdue invoices, records NEFT/UPI collections, and shows an ageing dashboard — flat annual subscription with no per-invoice charges.
Everything You Need to Collect and Recover GST Billing Fees
Built for Indian businesses — WhatsApp-first, UPI-native, AI-powered recovery
CGST/SGST/IGST auto-calculation. HSN/SAC codes, GSTIN on invoices. PDF download and WhatsApp send in one click.
All pending invoices per client in one view. Filter by overdue, partial, and paid.
Automated reminders on Day 1, 7, 15 after due date. Personalised with invoice details.
Escalating follow-up sequences for chronic defaulters — reminder → follow-up → final notice.
Record UPI/NEFT/cheque/cash against specific invoices. Partial payments tracked.
Outstanding by 0-30, 31-60, 61-90, 90+ days. Export for finance review.
Issue digital receipts on payment. GST-compliant, branded, shareable on WhatsApp.
Party-wise ledger statement. Share on WhatsApp or download PDF anytime.
How FastFee Works for GST Billing Businesses
- 1Add your business and GSTIN
One-time setup: GSTIN, business name, address, logo.
- 2Add clients
Client GSTIN, billing address, contact person, WhatsApp number.
- 3Create GST invoices
Add line items, HSN/SAC codes, tax rates. Invoice calculates CGST/SGST/IGST automatically.
- 4Send on WhatsApp
Send invoice as a PDF link directly to client's WhatsApp from the app.
- 5Track outstanding
Dashboard shows all pending invoices with due dates and ageing.
- 6Automated reminders
Set reminder schedules. FastFee sends WhatsApp reminders automatically on due date and overdue.
- 7Record collections
Mark invoices paid as payment arrives. Outstanding updates instantly.
Why Choose FastFee Over Generic Software?
| Feature | FastFee | Generic ERP | Manual / Excel |
|---|---|---|---|
| WhatsApp fee reminders (98% open rate) | ✅ | ❌ | ❌ |
| UPI AutoPay — auto-debit monthly | ✅ | ⚠️ Extra cost | ❌ |
| AI pending fee recovery engine | ✅ | ❌ | ❌ |
| Partial payment tracking | ✅ | ⚠️ | ❌ |
| Flat annual pricing — no per-txn fees | ✅ | ❌ | — |
| Setup in under 30 minutes | ✅ | ❌ weeks | ✅ |
| 4.7/5 rating from 214 reviews | ✅ | — | — |
Who Uses FastFee for GST Billing?
Frequently Asked Questions
What is the best GST billing software in India for small business?
FastFee is the best GST billing software for Indian small businesses in 2026. Unlike Vyapar or Tally, FastFee focuses on recovering dues faster with automated WhatsApp reminders — not just creating invoices.
How does FastFee GST billing software compare to Vyapar?
Vyapar is strong for inventory and accounting. FastFee is built for collection — automated WhatsApp reminders, overdue escalation, and ageing dashboards. FastFee works best for businesses with outstanding dues problems.
Can I send GST invoices and payment reminders on WhatsApp automatically?
Yes. Create the invoice, send it on WhatsApp, and set a reminder schedule. FastFee automatically sends reminder messages on Day 1, Day 7, and Day 15 after the due date.
Does FastFee GST software support CGST, SGST and IGST?
Yes. For intra-state transactions, FastFee splits tax as CGST + SGST. For inter-state, it applies IGST. You select the client state and the tax calculation is automatic.
Can I track multiple clients' outstanding in one dashboard?
Yes. The receivables dashboard shows all clients with pending invoices — total outstanding, oldest invoice, last payment date. Sort by amount or by days overdue to prioritize collection.
Ready to Automate GST Billing Fee Collection?
Join 10,000+ Indian businesses already using FastFee. Flat annual subscription — no surprises.