An inventory SOP (standard operating procedure) is a short written set of steps for each stock task: receiving, storing, moving, returning, counting and reordering. Each step names who does it and what record it leaves. It works because every person does the job the same way, so a mistake can be traced to the step that was skipped.
This guide shows what an inventory SOP covers, how to write one, and a template you can copy for a small shop. The worked example is a hardware store in Johannesburg, in rand.
What is an inventory SOP?
An inventory SOP is the written way your business handles stock, one procedure per task. It says what to do, in what order, who does it and what record proves it was done.
The US Environmental Protection Agency's guidance on writing SOPs gives the parts: a purpose, a scope, who is responsible, the steps, and the records kept. It also says a checklist is part of an SOP, not the SOP itself.
| Procedure | Purpose | Usually done by | Record it leaves |
|---|---|---|---|
| Receiving | Every delivery counted, checked and recorded the day it arrives | Storekeeper | Signed delivery note, purchase record |
| Storing | Every item in one labelled place, oldest or earliest-expiring in front | Storekeeper | Location on each product |
| Moving stock | Transfers between branches sent, approved and counted in | Storekeeper, manager | Transfer record |
| Returns and damages | Returned and damaged goods checked and recorded with a reason | Supervisor | Return or damage record with a note |
| Counting and adjusting | Records checked against the shelf, and corrected by someone else | Counter, then manager | Count sheet, adjustment with a note |
| Reordering | Low stock spotted daily and ordered on approval | Manager | Purchase order |
The SOP puts your inventory control rules into daily steps. The control decides who may adjust stock; the SOP says how, when and with what note.
What an inventory SOP saves: a worked example
An SOP saves money at the steps people skip when they are busy, and receiving is the first. Short deliveries signed for in a hurry are paid for in full.
For example, a hardware store in Johannesburg orders 40 bags of cement at R95 a bag, R3,800 in all. These are example figures, not a real store's.
- Without a receiving procedure: 38 bags arrive and one has split. The driver is in a hurry, the note is signed, and the store pays R3,800 for 37 bags it can sell. That is R285 lost on one delivery.
- With one: the storekeeper counts before signing, writes "38 delivered, 1 split" on the note, and both sign. The store records 37 bags and claims a R285 credit.
If one delivery a month goes wrong like this, that is R3,420 a year from one gap in one task. Short stock also means stockouts: the shelf runs out three bags before the records say it will.
The same holds for other tasks. TechTarget lists 20 common inventory problems, and several of them, such as ordering errors and reordering delays, are a skipped step.
How to write an inventory SOP in six steps
Write the SOP with the people who do the work, one task at a time, and test it before you rely on it. The six steps below follow the EPA's guidance.
Step 1: Organise the stock first
Give every item a home before you write about it. Label shelves and racks with short codes such as A1, group items by type, and keep one carton of each item open at a time.
Step 2: Decide how you will record stock
A paper stock book suits one person and a short list. A spreadsheet adds totals but not names. Inventory software records each movement as it happens, with who made it.
A shop needs records kept as goods move and counts that check them. Write both into the SOP: the record is updated at each step, and a count checks it on a set day.
Step 3: Write each task with the person who does it
Ask the storekeeper to walk you through a delivery and write down what they do. The EPA's guidance says SOPs should be written by the people who do the work.
Step 4: Keep each procedure to one page
Number the steps, start each one with a verb, and name who does it and what they record. The EPA asks for a concise, step-by-step format in the active voice.
Step 5: Test it with someone new
Give the page to a person who has never done the task and watch them follow it alone. The EPA's test is the same: someone with little experience should be able to do it unsupervised.
Step 6: Approve it, date it, post it
Give each procedure a number, a version and a date, and sign it off. Post a copy where the task happens: the receiving bench, the store room door, beside the till.
An inventory SOP template you can copy
Copy this template, change the names and the limits to your own, and print each procedure on its own page. Start every page with the same header.
| Field | Example |
|---|---|
| Number and title | INV-01 Receiving a delivery |
| Version and date | Version 1, 1 November |
| Purpose | Every delivery counted, checked and recorded the day it arrives |
| Scope | All supplier deliveries to the shop and the store room |
| Responsible | Storekeeper; the manager for deliveries over R10,000 |
| Records | Signed delivery note, purchase record, supplier's invoice |
| Approved by and review date | Owner; after any change, and within 12 months |
INV-01 Receiving a delivery
- Check the delivery note against the purchase order before unloading: supplier, items and quantities.
- Count every carton, and open one carton per line to check the pack size and contents.
- Check for damage, leaks and expiry dates. Refuse goods that expire within your limit, for example three months.
- Write any shortage or damage on the delivery note, and have the driver sign it with you.
- Record the purchase as received the same day, with the delivery note number in the note.
- Put the goods away the same day, new stock behind old.
INV-02 Storing stock
- Keep every item in its labelled place, and update the place on the record if it moves.
- Stack cartons at least 10 cm off the floor, 30 cm from the walls and no higher than 2.5 m.
- Put the earliest expiry date at the front, so it sells first.
- Keep damaged and returned goods on a marked shelf until they are recorded.
- Lock the store room; only the storekeeper and the owner hold keys.
The storage limits come from the USAID Logistics Handbook. Its 2.5 m limit is the height cartons can stand without crushing the ones below.
INV-03 Moving stock between branches
- The sending branch records the transfer and packs the goods with a copy of it.
- A manager approves the transfer before the goods leave.
- The receiving branch counts the goods against the transfer the day they arrive.
- Any difference is reported to the manager that day, before the transfer is closed.
INV-04 Returns and damages
- A supervisor takes customer returns, only against the original sale.
- Goods that can be sold go back on the shelf; damaged goods go to the marked shelf.
- Record each damage the day it happens, with what happened.
- Send faulty goods back to the supplier with a purchase return, and ask for a credit note.
INV-05 Counting and adjusting
- Count one category every week, on a rota that reaches every item.
- Print the count sheet without the system's quantities, so the count is blind.
- Count sealed cartons, multiply by the pack size, then add the open carton.
- Recount any line that differs by more than your limit, for example 2 units or R200.
- The manager corrects the stock with a note; the counter never adjusts their own count.
- Count everything once a year, before the books close.
Stock taking vs stock checking explains the kinds of count, and the inventory cycle count guide sets up the weekly rota.
INV-06 Reordering
- Each morning, read the low-stock list.
- Check what is already on order before ordering more.
- The manager approves each order and records it as ordered.
The inventory calendar
| How often | Task |
|---|---|
| Every day | Receive and record deliveries, read the low-stock list, record damages |
| Every week | Count one category; review adjustments, returns and damages |
| Every month | Check expiry dates; match purchases to supplier statements |
| Every year | Full count; review every procedure in the SOP |
How to train staff and keep the SOP current
Train with the SOP itself, and change it the day the work changes. A procedure nobody follows is worse than none, because it hides what people really do.
- Train with it. A new person does each task with the page in hand, watched for the first week. The one-week POS training plan follows the same pattern.
- Keep it where the work is. The EPA's guidance says current copies must be within reach of the people doing the task, on paper or on screen.
- Update it when anything changes. A new supplier, a new branch or new software changes the steps. Raise the version number and take the old copies down.
- Review it on a schedule. The EPA suggests every one to two years; a small shop should review once a year.
- Review it after a surprise. When a count finds a difference nobody can explain, find the step that failed and rewrite it.
How to run your inventory SOP in ArmPOS
Each procedure in the template matches a screen in ArmPOS, so the record the SOP asks for is made as the step is done.
| SOP step | In ArmPOS | Guide |
|---|---|---|
| Record an order, then receive it | Purchases › Create Purchase with Status ordered; Edit Purchase to received after the count | Record a purchase |
| Keep the supplier's invoice | Attach Documents on the purchase's menu | Record a purchase |
| Label shelves and racks | Settings › Warehouse Locations, then Internal Location on each product | Warehouse and locations |
| Move stock between branches | Transfer › Create Transfer, approved before stock moves; Sent, then Completed | Move stock |
| Take a customer return | Product Return in the POS, against the sale | Returns and refunds |
| Record damage | Damages › Create Damage, with a Note | Record damaged stock |
| Return goods to a supplier | Purchase Return on the purchase's menu | Return goods to a supplier |
| Count and adjust | Products › Count Stock by warehouse and category; Adjustment › Create Adjustment with a Note | Count and adjust stock |
| Read the low-stock list | Reports › Product Quantity Alerts | Reports to check every day |
The count sheet downloads as an Excel file with each product's quantity. Delete that column before you print it, and the count is blind.
For goods with expiry dates, track the product by batch. At the till, the batch that expires first sits at the top of the list. ArmPOS doesn't stop the sale of an expired batch, so INV-02 still matters (Batches and expiry dates).
On plans with the Knowledge Base, you can keep the SOP inside ArmPOS as your team's handbook. Each procedure becomes an article with numbered steps, and Versions keeps the earlier ones (Your team's handbook).
Frequently asked questions
What is an SOP in inventory management?
It is a written procedure for one stock task, such as receiving or counting. It lists the steps in order, who does each one and the record it leaves.
What should an inventory SOP include?
A header with its number, version, owner and review date, then the purpose, the scope, who is responsible, the numbered steps and the records kept.
How long should an inventory SOP be?
One page per task. If a procedure runs longer, it is probably two tasks, and staff won't read it at the receiving bench.
How often should an inventory SOP be reviewed?
Whenever the work changes, and at least once a year. The EPA's guidance suggests a periodic review every one to two years.
Who should write the inventory SOP?
The people who do the task, with the owner or manager approving it. Someone new should then test it by doing the task from the page alone.
Start with INV-01 this week: receiving is where the money goes first. When you want each step to leave its record without extra paperwork, create a free ArmPOS account.
