1. When one is required
An e-way bill is generally required for the movement of goods where the consignment value exceeds fifty thousand rupees, and it applies to movement rather than to sale — a stock transfer to your own second godown counts, as does goods sent for job work or on approval. Several states set a different threshold for movement within the state, and a few categories of goods are exempt. Confirm the limit that applies in your state with your CA, because it is not uniform.
2. Part A and Part B
Part A carries the transaction: your GSTIN and the buyer's, the invoice number and date, the value, HSN codes, and the places of despatch and delivery. Part B carries the transport: the vehicle number, or the transporter document number where a transporter is moving it. The bill is only valid once Part B is filled, which is the step most often missed when goods are handed to a transporter rather than sent on your own vehicle.
3. Validity, and the distance you enter
Validity is calculated from the approximate distance entered — broadly one day per two hundred kilometres, with different treatment for over-dimensional cargo. Understate the distance and the bill expires mid-journey; overstate it and you invite a question. On long runs into the hills or the north-east, where a load may genuinely take longer than the roads suggest, the distance and any extension need thinking about before the truck leaves rather than after.
4. When the vehicle changes
If the vehicle changes during the journey — a breakdown, a transhipment at a transporter's godown — Part B must be updated with the new number before the goods move further. A consignment travelling under a bill naming a different vehicle is effectively uncovered. This is where a proper delivery record earns its place, because you know exactly which bill and which load to update rather than working it out from a driver's phone call.
5. The mistakes that actually cost money
In practice, penalties come less from a missing e-way bill than from documents that do not agree: a vehicle number on the bill that differs from the one on the e-way bill, a quantity that does not match the invoice, or a value that does not tie. When the invoice, the challan and the e-way bill all come from one record they cannot drift apart. When they are assembled separately at the gate, they routinely do.
6. Making the entry quick
Every field the portal asks for already exists on a properly raised invoice with a delivery attached — value, tax, HSN codes, buyer details, despatch and delivery addresses, transporter and vehicle. If your billing captures those, the portal entry is copying from one screen to another rather than hunting through paperwork while a loaded truck waits at the gate.