Goods received notes, and why
stock should arrive on an order.

A goods received note, or GRN, is the record your own business makes at the door when a delivery arrives: what came in, how much of it, against which purchase order, on what date, and who checked it. It sits between the purchase order, which says what you asked for and at what price, and the supplier's invoice, which says what you are being charged. The three are matched line by line, and where they disagree, the payment waits until somebody has looked.

Three documents, and only one of them is yours

A delivery arrives with a delivery note. It is the supplier's document. It proves that a van left their yard with something on it and that somebody at your end signed for it, usually in the rain, usually without counting. It does not prove that what was on the pallet is what you ordered, and it says nothing about price.

The invoice arrives two or three weeks later. It is also the supplier's document. It says what they believe they delivered and what they believe you agreed to pay. By the time it lands the pallet has been broken down, the fittings are in bins or on a job, and the person who signed the delivery note is on a different site.

The purchase order is yours, if you raised one. It is the only record of what was actually asked for, in what quantity, at what price, for which job. Without it, the invoice is checked against a memory.

The goods received note is the fourth document and the one most small firms do not have. It is written by your side at the moment the goods are unloaded, and its only job is to say what actually arrived. Once it exists, the invoice can be checked against two facts instead of a recollection: what was ordered, and what turned up.

A delivery note proves a van turned up. A goods received note proves what was on it.

What to record at the door

Six things. The first four take under a minute per delivery once the order exists, because most of it is already on the screen.

1. The order it belongs to. The delivery is booked against a purchase order, not typed in fresh. That is what lets the system show the expected lines and quantities, and what makes the later match possible at all.
2. Each line and the quantity actually received. Not the quantity on the delivery note. Count the boxes, count the lengths. If twelve were ordered and eleven arrived, the record says eleven.
3. Shorts, substitutions and damage, recorded there and then. A different brand of valve, a split bag of adhesive, a missing bundle. Written at the door these are a note against a line. Discovered a fortnight later they are an argument with a supplier who has already invoiced.
4. Who checked it and when. A name and a date. This is the field that settles the dispute when the supplier says the goods were delivered in full.
5. Where it went. The bin, the shelf, the van, or the job. A quantity received with no location is a quantity that will be bought again, because nobody can see it.
6. The cost price it is booked at, taken from the order rather than from the invoice that has not yet arrived. This is how the cost of the job is known on the day the materials land rather than at month end, and how a price rise between order and invoice shows up as a difference rather than being paid quietly.

The three-way match, and what it catches

When the supplier's invoice arrives it is matched to the order and to the goods received note. Three documents, three sets of lines, and the arithmetic is done for you. Anything that does not agree is an exception to be looked at, and everything that does agree is approved for payment without anybody rereading it.

What it catches, in roughly the order of how often it happens:

• Billed but not delivered. The invoice carries twelve, the GRN says eleven. Without the GRN, twelve is paid, because the delivery note said twelve and nobody counted.
• Delivered at a higher price than ordered. The order said one figure, the invoice says another. Merchant price lists move several times a year, and the increase usually arrives on the invoice without a word. What to do when materials go up after you have quoted is its own article; the match is what tells you it has happened.
• Delivered but never ordered. The extra items added at the counter or over the phone because somebody was passing. Sometimes legitimate, sometimes not, always worth a question.
• Invoiced twice. A duplicate invoice with a new number for goods already matched and paid. The order has already been closed against the first invoice, so the second has nothing to match to.
• Coded to the wrong job. The order carries the job reference from the day it was raised. An invoice matched to it lands on that job, rather than being coded weeks later to whichever project looks most likely.

One thing the match does not do is decide the VAT treatment. A merchant supplying materials only charges VAT in the ordinary way; a subcontractor supplying labour and materials together may fall under the domestic reverse charge. That is covered in the reverse charge article, and it is the invoice, not the GRN, that HMRC will want to see.

The cost lands on the day, not at month end

The quieter benefit is what this does to job costing. A purchase order commits the money on the day it is raised. The goods received note confirms that the commitment became real goods, at the ordered price, on a known job. The invoice, when it comes, only settles what was already known.

So the cost of a job on any given day is the sum of what has been ordered for it, not the sum of the invoices that have happened to arrive. That is the difference between a cost report that is a week behind the site and one that is current to the last delivery, and it is the reason job costing spreadsheets break at exactly the point a firm starts buying for more than one job at once.

What it looks like when it is done every trading day

The clearest example on this site is not a contractor. C&G Heating & Plumbing Supplies are a merchant in Erith, Kent, with 72,444 stock lines behind a trade counter, and they have run stock, purchase orders and goods received notes on an inventory system built for them since November 2017.

The purchase order goes to the supplier from the same catalogue the counter sells from. When the delivery arrives it is booked in as a goods received note against that order, line by line, with shorts and substitutions recorded at the door. Every product carries a cost price as well as a sell price, and price movements are dated as they happen. The supplier's invoice then has two documents to be checked against instead of a memory, and the margin on a fitting is known before the accountant sees it.

None of that is peculiar to a merchant. A contractor's stores is a merchant with one customer: goods arrive against orders, get booked in, sit at a cost, and go out to jobs instead of across a counter. The paperwork is the same; only the direction of the last movement changes. Stock control for a contractor follows the goods from that door to the van and the job.

Is it worth it for a small firm

The honest answer is that it depends on three things. Whether you buy on account at more than one merchant. Whether materials go to more than one job at a time. And whether the person who checks the invoices is somebody other than the person who ordered the goods.

If the answer to any of those is yes, the checking is already happening, badly, in somebody's head, and the goods received note is not extra paperwork. It is the same work done once at the door instead of three times in the office. If the answer to all three is no, a single buyer with a single job can hold it in their head for a while longer, and knows roughly when that will stop being true.

Where to start, on Monday

Do not start by choosing software. For the next ten deliveries, whoever signs the delivery note writes the purchase order number on it, counts every line, and marks any difference before the driver leaves. Then compare those ten notes with the invoices when they arrive.

Most firms doing this for the first time find a difference on at least one of the ten, and it is almost never in their favour. That difference, multiplied by a year of deliveries, is the size of the problem, and it is also the number that tells you whether a goods received note is worth thirty seconds at the door.