Long jobs are rarely billed once. Thirty per cent on order, forty on delivery, thirty on commissioning is an ordinary arrangement — and it is where most billing errors live, because somebody is keeping the running total in a note.

This is off until you switch it on. Most businesses bill in full, and an extra step on every invoice for the sake of the few who do not is the wrong trade. Turn it on in Settings when you need it.

The five ways

Mode	Bills	Use when
Full	Everything.	The ordinary case.
Remainder	Whatever is still unbilled.	The last invoice on a job.
Amount	A rupee figure you name.	Milestones agreed in money.
Percentage	A share you name.	Milestones agreed in per cent.
Per line	Different amounts on different lines.	Some items delivered, others not.

How an amount is spread

Name a rupee figure and it is spread across the lines in proportion to what each still has outstanding. A line already billed in full is not billed again just to make the total come out.

Fixed-price work

This is the part worth reading twice. A third of a fixed-price job is not a third of one unit — the quantity is still one. So the quantity is left alone and the rate carries the fraction.

The line then reads 33.33% of the quoted ₹1,00,000. A customer holding a quotation for a lakh and an invoice for thirty-three thousand is owed that sentence; without it the invoice looks like a different job.

A flat discount on the line scales with the fraction.
Freight is billed as the same share — freight on a third of the job is a third of the freight.

An example

A sales order for ₹10,00,000 of installation work.
On order: invoice at 30%. ₹3,00,000. Each line reads as 30% of its quoted rate.
On delivery: invoice at 40%. ₹4,00,000.
On commissioning: invoice the remainder. It works out ₹3,00,000 without anybody adding up.
The order is now fully invoiced and says so.

What it prevents

Billing the same work twice, because the running total is not in somebody’s note.
Quietly under-billing. A job that finishes at eighty per cent billed is visible rather than discovered at year end.
Arguments, because the invoice says what share of what it is.

Where to go next

Next in sales documents Let customers pay online → Convert a proposal to a quotation, sales order or invoice →

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