Category: Store Operations

SKU, UPC, EAN, GTIN — retailers use these terms interchangeably, but they are not the same thing. Mixing them up leads to duplicate products, barcodes that scan the wrong item, and marketplaces rejecting your listings.

This guide explains what each identifier is, who issues it, how the barcodes differ, how check digits work, and how to set up product identification correctly in a store — with a comparison table and a list of common mistakes.

The short answer

What is a SKU?

A SKU is an identifier you create to track products in your own inventory. Two shops can sell the same can of soup under completely different SKUs. Because SKUs are internal, you can design them to be meaningful to your team — for example TEA-GRN-100 for 100 g of green tea.

Good SKU design rules

• One SKU per sellable variant (size, colour, pack size) that you need to count or price separately.
• Keep them short and unambiguous — avoid letters that look like numbers (O and 0, I and 1).
• Don’t encode things that change, such as price or supplier; use fields for those.
• Never reuse a SKU for a different product, even after the old one is discontinued.

A SKU is not automatically a barcode. If you want to scan an internal SKU, you print it as a barcode on your own labels — see barcode labels.

What is a GTIN?

The GTIN is the globally unique product number defined by GS1, the not-for-profit organisation that manages barcode standards. A brand owner licenses a GS1 Company Prefix from its national GS1 organisation and uses it to number its products. Retailers, marketplaces and distributors then use that number to identify the product everywhere.

A GTIN has three parts: the GS1 Company Prefix identifying the brand owner, an item reference chosen by the brand for each product, and a final check digit that lets scanners and systems detect typing or reading errors. GS1 guidance is that a materially changed product should receive a new GTIN, and that outer cases usually have a different GTIN from the individual consumer unit.

UPC, EAN and the GTIN family

Modern POS scanners in most countries read both UPC-A and EAN-13. A 12-digit UPC can be represented as a 13-digit number by adding a leading zero, which is why systems often store GTINs as 14 digits padded with zeros. If your store sells imported and local goods, make sure your POS treats 036000241457 and 0036000241457 as the same product.

How the check digit works (with an example)

All GTIN lengths use the same mod-10 check digit. Starting from the rightmost data digit (excluding the check digit), multiply digits alternately by 3 and 1, add the results, and choose the check digit that brings the total to the next multiple of 10.

Example: the 12-digit UPC-A 03600024145? — find the last digit.

1. Digits in odd positions from the right (0, 6, 0, 2, 1, 5): sum = 14, × 3 = 42.
2. Digits in even positions from the right (3, 0, 0, 4, 4): sum = 11.
3. Total = 42 + 11 = 53. The next multiple of 10 is 60, so the check digit is 60 − 53 = 7.
4. Full code: 036000241457.

Another commonly used example: the first 12 digits 400638133393 give a weighted sum of 89, so the EAN-13 check digit is 1 (4006381333931). A scan that fails this test is rejected, which is why mistyped barcodes rarely match a wrong product.

In-store and variable-measure barcodes

Not every product comes with a GTIN. For items packed or weighed in the shop, GS1 reserves Restricted Circulation Numbers (RCNs) — for example 13-digit numbers starting with 02 or 20–29 — whose meaning is defined by the local GS1 organisation or by the company, not globally. They are commonly used for:

• Products weighed and priced in store (deli, meat, cheese, bulk foods) — where the barcode can contain a price or weight field according to local rules.
• Internal items such as bakery products made on site.
• Store coupons and vouchers, depending on local rules.

Because the layout of these codes varies by country and by retailer, check your local GS1 organisation’s rules and confirm what your POS and scales support before relying on weight- or price-embedded barcodes. For simple unbarcoded items, many small shops just print internal barcodes from their SKUs.

Product labels and shelf labels

Print labels from the same product record the till uses, so shelf price and checkout price can’t disagree. See barcode and price labels.

Scanners and barcode types

Most retail scanners read UPC-A, UPC-E, EAN-13 and EAN-8 out of the box. A few practical points:

• 1D vs 2D: linear scanners read classic barcodes; 2D imagers also read QR codes and GS1 DataMatrix, and screens on phones.
• ITF-14 and GS1-128 on cartons may need to be enabled in the scanner’s settings if you scan cases at receiving.
• Keyboard mode: most USB scanners type the digits into the active field followed by Enter.

For setup and troubleshooting, see the POS hardware setup checklist and the barcode scanner page.

How to set up product identification in your store

1. Create a SKU for every sellable variant following your naming rules.
2. Store the manufacturer GTIN on the SKU for every product that has one — scan it rather than typing it.
3. Generate internal barcodes for products without a GTIN and print labels.
4. Check for duplicates: no two SKUs should share a barcode.
5. Test at the till: scan ten random products and confirm the right item and price appear.
6. Record case GTINs separately if suppliers deliver in scannable cartons.

This identification layer underpins everything else in inventory management — see the retail inventory management guide and inventory management.

When a barcode won’t scan

1. Check the symbol: damaged, wrinkled or poorly printed barcodes are the most common cause. Try a different angle or a 2D imager.
2. Check the scanner settings: some symbologies (for example ITF-14 or GS1 DataMatrix) may be disabled by default.
3. Check the product record: the barcode may not be stored on any SKU, or stored with a missing leading zero.
4. Type the number as a fallback, then fix the record so the next scan works.
5. Relabel the product with an internal barcode if the printed one is unreadable.

Common mistakes

Frequently asked questions

Related guides

• Retail inventory management guide
• POS hardware setup checklist
• Inventory cycle counting
• Retail store operations guide

Sources and further reading

• GS1 UK — FAQ on GTINs and barcodes
• GS1 — Restricted Circulation Numbers (GSCN 23-006)
• GS1 — Summary of GS1 MO prefixes 20–29
• GS1 New Zealand — Bar coding basic user guide
• Wikipedia — International Article Number (check digit examples)

Customers judge a shop by the moments they see — a tidy entrance, a quick checkout, a product that is actually on the shelf. Those moments are the result of routines nobody sees: the opening checks, the cash float, the delivery checked at the back door, the reports reviewed after closing. That set of routines is retail store operations.

This guide walks through a complete store day, from the first key in the door to the last report, with responsibilities, checklists and standard operating procedures (SOPs) you can adapt to your own shop.

What retail store operations cover

Store operations are the repeatable tasks that keep a shop safe, stocked, staffed and profitable. They fall into five groups:

Opening procedures

The first 30 minutes set the tone for the day. A written opening checklist means the store opens the same way regardless of who holds the keys.

• Disarm the alarm and check doors, windows and the stockroom for signs of a break-in.
• Switch on lights, music, heating or air conditioning and the POS equipment.
• Start the POS and confirm it loads, the receipt printer works and the cash drawer opens.
• Count the opening float into the drawer and record the amount.
• Check yesterday’s handover notes: deliveries due, customer orders, problems to follow up.
• Walk the sales floor: fill gaps, face up shelves, check price labels and promotions.
• Check the entrance, floor and fitting rooms for safety hazards.
• Brief the team: targets, promotions, deliveries and who covers breaks.

Opening the till and the cash drawer before customers arrive catches hardware problems early — see the POS hardware setup checklist for fixes to common issues.

Employee responsibilities

Clear ownership prevents tasks from falling between people. Even in a team of two or three, name who is responsible for each area on each shift.

Give every person their own login so sales, refunds and adjustments are attributed correctly, and match permissions to the role — see staff, roles and permissions.

Running the checkout

The checkout is where most customers form their final impression. Standards worth writing down:

• Greet and acknowledge every customer, including those waiting in the queue.
• Scan every item individually — even identical-looking variants — so stock stays accurate.
• Confirm the total on the customer display before payment.
• Count change back and keep notes on the drawer ledge until change is given.
• Offer the receipt, and reprint from sales history if a customer needs one later.
• Queue rule: call for a second till when more than three customers are waiting.

Returns and exchanges

Write a short returns SOP: proof of purchase, time limit, condition check, who can approve refunds, and how returned stock is recorded (back to stock or written off). Consistent handling protects customers and the business — the shrinkage prevention guide explains why.

Learn more about the checkout screen on the point of sale page.

Receiving stock during the day

Schedule deliveries for quieter hours where suppliers allow it, and keep one person responsible for each delivery.

1. Check the delivery note against the purchase order.
2. Count cases (and units for high-value items) before signing; note shortages and damage on the paperwork.
3. Record the delivery in the system the same day, with quantities and cost prices.
4. Print labels for unbarcoded or repriced items.
5. Move stock to the sales floor or its stockroom location; don’t leave cartons in aisles.

For a deeper process, see the retail inventory management guide and purchase management.

Mid-day routines

• Replenish fast movers from the stockroom before peak periods.
• Check the low-stock list and prepare supplier orders — see reorder point formula.
• Run today’s cycle counts during a quiet hour — see inventory cycle counting.
• Do a safe drop if cash in the drawer exceeds your limit.
• Tidy and re-face displays after busy periods.
• Cover breaks so the till is never unattended.

Closing procedures

Closing combines money, stock and security. A checklist matters here more than anywhere, because tired staff skip steps.

• Lock the entrance at closing time and serve remaining customers.
• Complete the cash-up: count the drawer, compare with the expected amount, record any difference — see cash register reconciliation.
• Settle or close the card terminal batch if your provider requires it.
• Put the next day’s float and the banking in the safe.
• Run the end-of-day report in the POS.
• Tidy the floor, empty bins, check fitting rooms and toilets.
• Write handover notes for the opening team.
• Switch off equipment that should not run overnight; leave the main POS computer on if it runs backups.
• Set the alarm and lock up.

Daily reports to review

Five minutes with the right numbers each evening or morning prevents small problems from becoming big ones.

Track a handful of headline metrics weekly as well — the retail KPIs guide lists twelve worth following. Report options are described on the reports and analytics page.

Writing standard operating procedures (SOPs)

An SOP is a short, written description of how a task is done in your store. It makes training faster and quality consistent. Keep each SOP to one page:

Start with the SOPs that cause the most problems when done badly: cash-up, refunds, receiving, opening, closing and handling an internet or power outage. The offline vs cloud POS article includes an outage procedure you can adapt.

Onboarding new employees

New staff learn a store’s routines fastest when training follows the same structure as the day itself. A simple first-week plan:

Give the new employee their own login from day one with limited permissions, and widen permissions as they are trained. Using demo data on a spare device is a low-risk way to practise refunds and corrections.

Handling incidents

Every store eventually faces a power cut, an internet outage, a broken card terminal, a customer complaint or a suspected theft. Decide in advance who handles each and what they do:

Record each incident in the handover log so patterns become visible.

Weekly and monthly routines

Frequently asked questions

Related guides

• Cash register reconciliation
• Retail KPIs
• Retail inventory management guide
• What is a POS system?

Sources and further reading

• Taqtics — Cash drawer reconciliation checklist
• StoreHub Help — Shift report: cash drawer over/short, pay-outs and cash sales

At the end of every trading day, one question matters more than any other in the back office: does the cash in the drawer match what the till says should be there? Cash register reconciliation answers it — and when it is done the same way every day, it catches mistakes within hours instead of weeks.

This guide explains the expected cash formula, walks through a complete worked example, covers refunds, paid-outs and safe drops, shows how to investigate differences, and ends with a closing procedure and a template you can copy.

Key terms

The expected cash formula

Only cash movements belong in this formula. Card, mobile wallet and account (credit) sales are reconciled separately against the card terminal and customer balances.

Worked example: closing a single drawer

A gift shop starts the day with a $150.00 float. The POS end-of-day report shows:

The closing cashier counts $862.50. Over / short = 862.50 − 867.50 = −$5.00 (short).

What goes to the bank?

1. Keep the float for tomorrow: $862.50 − $150.00 = $712.50 to deposit from the drawer.
2. Add the safe drop: $712.50 + $500.00 = $1,212.50 total cash to bank.
3. Check: net cash takings were $1,284.50 − $42.00 − $25.00 = $1,217.50. Banked $1,212.50 + $5.00 shortage = $1,217.50 ✓

How to count the drawer accurately

1. Count in a secure, quiet place away from customers — ideally after closing.
2. Count by denomination, largest notes first, and write each subtotal on the count sheet.
3. Count coins by weight or in rolls where possible.
4. Separate the float first (use a fixed mix of small notes and coins) and bag it for tomorrow.
5. Count the remaining cash — that is the deposit.
6. For larger amounts or any difference, have a second person recount.

Reconciling card and other payments

Cash is only part of the day. Reconcile each payment method against its source:

A frequent pattern: cash is short by exactly the amount that card is over. That usually means a cashier selected the wrong payment method, not that money is missing. Recording the correct payment method on every sale makes daily reconciliation straightforward — see the point of sale page.

Investigating differences

Small differences happen; unexplained patterns are what matter. Work through this list before recording a difference:

1. Recount the drawer, preferably by a second person.
2. Check payment methods: any card sale recorded as cash, or the reverse?
3. Check paid-outs and safe drops: all recorded, with receipts and the correct amounts?
4. Check refunds and voids: any refund given in cash but recorded to card, or not recorded at all?
5. Check the float: was it the agreed amount this morning?
6. Review the sales log for unusual discounts or no-sale drawer openings.

Record the final difference honestly — never “fix” it by adjusting another figure, and never net unrelated overages and shortages. Over time, differences by cashier and by day reveal training needs or problems. Individual logins and an activity log make this review possible — see staff permissions and activity log.

End-of-day closing procedure

• Close the last sale and lock the entrance.
• Run the POS end-of-day (or shift) report.
• Settle or close the card terminal batch if required by your provider.
• Separate and bag tomorrow’s float.
• Count the remaining cash by denomination on the count sheet.
• Calculate expected cash and over/short; recount if there is a difference.
• Reconcile card, account and voucher totals.
• Record the result, sign the sheet (two signatures for differences above your threshold).
• Prepare the bank deposit with the deposit slip; store it and the float in the safe.
• Note anything unusual in the handover log.

This routine sits inside the wider closing checklist in the retail store operations guide.

Reconciliation template

Copy this into a spreadsheet or print it as a daily sheet:

Multiple drawers and shift changes

When several tills or shifts share a day, reconcile each drawer separately. Combining everything into one daily total hides who handled which cash and makes differences impossible to trace.

• Shift change: the outgoing cashier counts and signs off their drawer; the incoming cashier starts with a fresh, counted float.
• Shared drawer (unavoidable in very small shops): count at every handover and record both names.
• Multiple tills: run a shift or end-of-day report per terminal where your POS supports it, and keep one count sheet per drawer.

Safe and banking routines

• Keep a safe log: every drop, float and deposit with date, amount and initials.
• Vary banking times and routes and avoid carrying large amounts alone.
• Match deposits to bank statements weekly; a deposit that never reaches the account is a serious red flag.
• Limit safe access to keyholders, and change codes when staff leave.

Training cashiers for accurate cash handling

Most cash differences come from small habits rather than dishonesty. Train every new cashier on the same routine: state the amount received out loud, place the customer’s note on the drawer ledge until change is given, count change back from the total, and close the drawer between transactions. Teach them to record every refund and paid-out in the POS immediately, never “later”.

Practise a full cash-up together during the first week, including a deliberate difference to investigate. A cashier who has traced a mistake once understands why each record matters — and is far more likely to keep the drawer accurate when nobody is watching.

Controls that reduce cash differences

• One drawer, one cashier per shift where possible.
• Blind closing: the cashier counts without seeing the expected figure; the manager compares.
• Limits: safe drops when the drawer exceeds a set amount.
• Receipts for every paid-out and a log of who approved it.
• Refund rules: cash refunds only for cash sales, with manager approval above a threshold.
• Review weekly: over/short by cashier and by day.

For a broader view of losses, see retail shrinkage prevention, and for a daily overview of sales by payment method, see reports and analytics.

Frequently asked questions

Related guides

• Retail store operations guide
• Retail shrinkage prevention
• Retail KPIs
• Margin vs markup

Sources and further reading

• StoreHub Help — Shift report: cash drawer over/short, pay-outs and cash sales
• Meevo Docs — Register calculations
• Taqtics — Cash drawer reconciliation checklist
• Open Exam Prep — Day-end reports, payment method reconciliation and cash over/short