GST and billing, explained like a human.
Practical guides for Indian business owners — written by the team that had to encode these rules into software, so every edge case has been argued about already.
GST Guides
B2B, B2C Small, B2C Large, Export: How Every Invoice Gets Classified
Why GSTR-1 sorts every sale into one of four buckets, and what decides which one an invoice lands in.
Invoice Numbering Rules Under GST: What's Allowed, What Breaks an Audit
The numbering habits that pass a GST audit without a second look, and the ones that invite one.
HSN Codes: How Many Digits You Need, and Where They Must Appear
HSN digit requirements scale with turnover — here's how to find your bracket and apply it consistently.
Input Tax Credit for Small Businesses: What Qualifies, What Silently Doesn't
The purchases that build your input credit, and the quiet exclusions that shrink it without anyone noticing.
GST Invoice Format Explained (With a Free Checklist)
Every field a GST-compliant tax invoice needs, and the mistakes that get invoices rejected during audit.
GSTR-1 vs GSTR-3B: What Small Businesses Actually File
The difference between GSTR-1 and GSTR-3B, who needs to file what, and how to avoid the most common mismatch.
Delivery Challan vs Invoice: When Goods Can Travel Without a Bill
The situations that legally require a delivery challan, and how to turn a stack of them into one clean invoice.
Credit Notes and Debit Notes, Explained Without the Confusion
When you must issue a credit or debit note, what each needs to contain, and the reporting deadline that catches businesses out.
Receivables Aging: Reading the Report That Predicts Your Cash Crisis
A simple system for tracking what you're owed, spotting trouble early, and never missing a follow-up.
Expense or Purchase Bill? Where Each Outgoing Belongs in Your Books
A simple test for the one decision that quietly determines whether your reports and your ITC are accurate.
Stock Registers for Small Shops: Paper vs App
Why a paper stock register breaks down as a shop grows, and what actually changes when it moves to an app.
From the blog
Why We Built LedgrBook
July 27, 2026The gap we kept seeing between how small businesses actually keep books and what billing software assumed they'd do.
What "GST-First" Means in Practice
August 3, 2026GST-first isn't a report you generate at month-end — it's a decision baked into how every document is structured.
LedgrBook v1: What's In, What's Not, What's Next
August 10, 2026An honest scope note on the first release — what LedgrBook does today, and what we're deliberately not claiming yet.