Shopify blog
Product availability means having the right item in stock when and where a customer wants to buy it. According to 2025 data from IHL Group, inventory distortion—the discrepancy between the amount of stock recorded in your system and the actual amount on your shelves—costs retailers more than $1.7 trillion worldwide each year. The same report says that poor availability can cost your business sales and weaken customer trust.
Take, for example, a shopper looking for a winter coat before a forecasted snowstorm. They researched the coat online and arrived ready to buy, but it’s missing from the rack and stockroom. If store associates can’t say when it will return, the shopper will likely buy elsewhere.
This guide explains three key product availability metrics and how to improve inventory levels and management before stockouts cost you a sale.
What is product availability?
Product availability measures whether items are in stock and available for purchase when customers want to buy them. It’s a fundamental retail metric that tracks your ability to meet customer demand at the point of sale, whether through a brick-and-mortar store, online retailer, or other sales channels.
When product availability is high, customers find what they need and complete their purchases. When it’s low, you lose sales, frustrate shoppers, and risk long-term damage to your business.
Why product availability matters for customer loyalty and sales
When products are unavailable or hidden in the back of a warehouse, missed transactions add up, and the damage extends far beyond a single lost sale. In a 2025 SPAR Group survey, 74% of shoppers ranked product availability as their top in-store priority, above both price and promotions.
Strong product availability delivers three business advantages:
- Customer satisfaction and loyalty. Customers expect to find what they need when they’re ready to buy, and may lose trust in your brand if they encounter regular stockouts. This erosion of trust compounds over time.
- Competitive advantage. Supply chain bottlenecks and demand-forecasting errors affect every retailer, but those who consistently maintain inventory positively influence customer expectations, training shoppers to visit them first.
- Operational efficiency. Planned replenishment takes less time and costs less than responding to unexpected stockouts. Accurate forecasts promote operational efficiency, helping reduce rush orders and decrease inventory.
Common causes of poor product availability
Poor product availability typically stems from four main causes, including:
- Supply chain disruptions
- Inaccurate demand forecasts
- Inefficient inventory management
- Supplier issues
Supply chain disruptions
Supply chain disruptions extend lead times and make delivery dates less reliable. In KPMG’s 2025 Global Consumer & Retail CEO Outlook, 52% of the 120 consumer and retail CEOs surveyed named supply chain resilience as the biggest challenge driving short-term decisions.
Problems can emerge at any stage of the supply chain. Some of the most common issues include:
- Raw material shortages, which can force suppliers to pause production or switch to alternative materials, requiring new sourcing relationships and quality tests.
- Natural disasters, which can halt manufacturing in affected regions and create transportation bottlenecks that persist for weeks after the immediate crisis ends.
- Regulatory changes, which may suddenly require additional product testing to clear customs, turning a predictable two-week lead time into a six-week uncertainty.
- Supplier capacity constraints, which can become critical during peak seasons when your vendors serve multiple retailers competing for the same production slots.
These supply chain disruptions turn once-stable lead times into moving targets, making consistent product availability nearly impossible to achieve without significant safety stock reserves.
Inaccurate demand forecasting
Poor demand forecasting increases the risk of stockouts and turns manageable variability into business-threatening availability gaps. The challenge grows when external factors shift customer behavior in ways historical data can’t predict.
Consider this scenario: You forecast 4,000 units for Black Friday based on last year’s sales and market trends, and current inventory velocity. But then a TikTok video featuring your product goes viral three days before the sale. Your entire inventory—including safety stock—sells out in the first few hours, creating a stockout during the year’s most critical shopping weekend. Your forecasting wasn’t wrong based on available data, but it couldn’t account for an unpredictable viral demand spike.
Here are some common scenarios that can challenge effective forecasting:
- Seasonal prediction errors, such as under- or overestimating peak period demand
- New product launches that have you guessing initial order quantities because you don’t have historical data to reference
- Surprise demand surges when marketing campaigns perform better than expected
AI-powered forecasting tools can help analyze patterns across multiple data sources to improve prediction accuracy, but inventory forecasting remains one of the most complex variables affecting product availability.
Inefficient inventory management
Manual processes and disconnected systems create blind spots that make it difficult to maintain reliable product availability. When your inventory data doesn’t reflect reality, every downstream decision—from reorder timing to promised delivery dates—starts from a flawed foundation.
Offbeat Bikes encountered this problem before unifying its store and online inventory.
“If a bike or a certain part had just sold out at the shop, our online shoppers weren’t necessarily aware of that. That led to us overselling items and having to manually cancel orders and issue refunds,” says Owner Mandalyn Renicker.
Inefficient inventory management can happen for several reasons, including:
- Poor inventory visibility across sales channels. Online systems don’t reflect what’s actually on store shelves. Meanwhile, store associates can’t see warehouse availability when customers request items.
- Manual process errors. Human data entry introduces mistakes during receiving, transfers, and cycle counts.
- Disconnected systems. Retailers reconcile inventory across separate platforms for ecommerce, point of sale (POS), and warehouse management, creating gaps where products exist physically but appear unavailable digitally, or vice-versa.
Unlike external supply chain disruptions, inefficient inventory-management practices are internal, controllable factors. Tracking finished goods through unified systems addresses the underlying issue, allowing you to stay on top of inventory and reduce the risk of poor product availability.
Supplier issues
Retailers depend on supplier reliability and flexibility to maintain consistent product availability, but vendor relationships introduce variables outside your direct control. Even strong supplier partnerships face challenges that can disrupt inventory flow and create stockouts, including:
- Contract negotiation delays. When your initial supplier contract expires and new pricing negotiations extend for days or weeks, you may hesitate to place orders under uncertain terms. This may affect how quickly you receive inventory or threaten product availability for items approaching stockout levels.
- Minimum order quantity (MOQ) constraints. If your supplier requires 200-unit orders but you only need 50 units urgently to bridge a gap, you must choose between a stockout and excess inventory.
- Limited supplier diversification. Many retailers experience limited supplier choices, which means a problem with one vendor can’t be quickly resolved by switching to an alternative.
- Lead-time inconsistency. The same supplier delivers in two weeks one time and five weeks the next, making reliable reorder point calculations nearly impossible.
How to measure product availability
Supply chain KPIs provide the visibility needed to identify problems before they become revenue-threatening stockouts, but product availability specifically requires three complementary metrics that each reveal different aspects of your inventory performance.
| Metric | What it measures | Formula |
|---|---|---|
| Stockout rate | Unmet purchase attempts | Stockouts / sales opportunities x 100 |
| On-shelf availability | Recorded stock on shelves | Shelf units / expected units x 100 |
| Inventory turnover | Rate inventory sells | COGS / average inventory value |
Stockout rate
Stockout rate measures the percentage of recorded purchase attempts that could not be fulfilled because an item was unavailable. It can be tracked by product SKU and location to identify recurring stockouts.
Fill rate measures the percentage of customer orders fulfilled from available inventory. Together, the two metrics compare unmet demand with completed orders.
Here’s how to calculate stockout rate:
Formula: Stockout rate = (number of stockout instances / total sales opportunities) x 100
Example: Your store receives 100 orders for a T-shirt but can fulfill only 95. The other five orders count as stockouts. Your stockout rate is (5 / 100) x 100 = 5%.
Compare the rate over time; an increase can indicate late replenishment or unreliable supply.
On-shelf availability (OSA)
On-shelf availability measures whether inventory recorded at a store is available on the sales floor. An inventory system may report strong store availability, even when those products remain in the stockroom, out of shoppers’ reach.
Here’s how to calculate OSA:
Formula: OSA = (units available on shelf / units expected on shelf) x 100
Example: Your inventory system records 50 candles at one store. An audit finds 40 on the shelf and 10 waiting in the stockroom. The store’s OSA is (40 / 50) x 100 = 80%.
Low OSA can indicate delays between receiving inventory and shelving it. Compare OSA by location to determine where recorded stock is not reaching the sales floor.
Inventory turnover
Inventory turnover tracks how many times a retailer sells through its average inventory during a set period. A high turnover ratio can increase stockout risk when replenishment falls behind demand. Low turnover ties up capital and raises carrying costs.
Here’s how to calculate inventory turnover:
Formula: Inventory turnover = cost of goods sold (COGS) / average inventory value
Example: Your annual COGS is $600,000, and your average inventory value is $100,000. Your inventory turnover is $600,000 / $100,000 = 6. The business sells through its average inventory about once every two months.
Turnover targets vary by product category and supplier lead time. Use the stock-to-sales ratio for a more current view of your inventory position.
How to check product availability across channels
Product availability varies by location and sales channel. An item may be in stock at one store but unavailable online because that store does not fulfill online orders. Check the product record before confirming availability with a customer.
Review inventory by location
Open the product record in Shopify and review the available quantity for each location. Shopify tracks inventory separately at every store and fulfillment location.
Available inventory is product that can still be sold. On-hand also counts units already committed to orders or placed in an unavailable state. Compare the recorded quantity with a physical count when the numbers look wrong.
Check each sales channel
Confirm that the product is active on the channel where the customer found it. Then check whether the location holding the stock can fulfill orders from that channel.
A retail-only location may have available inventory that does not count toward online availability. Product publishing settings can also prevent an in-stock item from appearing on the online store, shop, or another sales channel.
Resolve availability discrepancies
Incorrect counts and unfinished transfers commonly cause availability discrepancies. Inventory assigned to the wrong location can create the same problem. Review the product’sinventory status before adjusting its quantity. Damaged units, safety stock, and incoming inventory are not available for sale.
Offer another fulfillment option
Store staff can use the Shopify app to check available inventory at other locations. If another store has stock, offer pickup at that location via Shopify POS Pro, which lets staff create pickup orders for another eligible store. They can alsoship the order to the customer from the register.
How to improve product availability
Measuring product availability can reveal problems, but solving them requires implementing targeted strategies that will address the root causes. The most effective approach balances stockout prevention tactics with operational practices that catch issues before they impact customers.
Conduct regular inventory audits
Regular audits catch discrepancies between recorded and actual inventory quantities before they cause unexpected stockouts. When your system shows 500 products but physical counts reveal only 450, that 50-unit gap means items will become unavailable sooner than anticipated.
Inventory shrinkage—from internal theft, shoplifting, or return fraud—creates discrepancies that erode product availability over time. Addressing shrinkage protects future inventory levels and prevents a compounding effect, where small losses accumulate into significant stockouts.
Compared with full physical inventories, where you count everything at once on a quarterly basis, cycle counting—continuously auditing small portions of inventory—catches problems faster because you audit high-value or fast-moving items weekly.
Inventory-management technology can help eliminate manual counting errors and accelerate the audit process through automation:
- Barcodes store product information that updates your inventory-management system instantly when scanned during cycle counts or at checkout.
- RFID tags enable rapid scanning of multiple items simultaneously, improving inventory accuracy to over 98%, according to National Retail Federation (NRF) research.
- Real-time synchronization ensures your system accounts for each scan immediately, eliminating lag between physical counts and recorded quantities.
Shopify lets you track inventory quantities by location and unifies this data in a central operating system, so you’ll never oversell items that are out of stock or make promises based on inaccurate availability data.
Configure automated reordering
Automated reordering eliminates the timing guesswork that causes overstocking or stockouts. Place purchase orders too early and you tie up capital while paying unnecessary carrying costs. Place them too late and products become unavailable before replenishment arrives.
Just-in-time (JIT) inventory management defines an optimal reorder point where you order new products precisely when needed to maintain availability without holding excess stock. The calculation considers your average sales velocity, supplier lead times, and desired safety stock buffer to account for demand variability or delivery delays.
When inventory quantities drop into low stock territory, your inventory-management tool automatically triggers reordering before stockouts occur. Automation primarily benefits retailers managing hundreds or thousands of SKUs, where manual reorder tracking becomes impossible to maintain consistently across your entire catalog.
Implement demand-based forecasting
Demand-based forecasting estimates future orders from past sales and known events, such as an upcoming promotion. Stores use the forecast to set purchase quantities and reorder dates. In NVIDIA’s 2026 retail and CPG AI survey, 51% of respondents said their companies used AI for supply chain operational efficiency and throughput.
Shopify’s order forecasting uses historical sales data to predict demand, with Shopify sales and inventory reports providing supporting data. The inventory sold daily by product report, for example, shows how quickly each variant has sold during a selected period.
Starlight Knitting Society uses sales and marketing data when placing inventory orders.
“Tracking where our sales are coming from, and understanding which types of promotions and advertisements actually bring in sales, has changed the way I have been ordering inventory. We can better accommodate what our customers are looking for,” says shop owner Melissa Nelson.
Compare forecasts with actual sales before placing the next order. Update them when promotions, customer demand, or supplier lead times change.
Maintain strong supplier relationships
Your ability to maintain a continuous supply hinges on your relationships with suppliers. When they feel valued, they’ll be more willing to contribute solutions to challenges that threaten product availability.
For example, say you miscalculated demand and sold your denim jeans inventory faster than forecast. Your supplier’s standard lead time is two weeks for new production runs, but you need inventory within days to prevent a complete stockout during peak selling season. A strong relationship with your supplier might make it easier to negotiate a solution.
One way to maintain vendor relationships is through supplier scorecards, where you track performance on lead-time consistency, quality standards, and responsiveness. This data-driven approach identifies which suppliers warrant deeper partnerships and which need backups and alternatives.
Diversifying your suppliers for critical products gives you fallback options when primary suppliers face capacity constraints or quality issues. Keep in mind that relationships can also suffer when orders are spread too thin across too many vendors.
Regular communication, transparent forecasting, and fair negotiations during contract renewals build the trust that translates into flexibility when product availability challenges arise.
Streamline returns logistics
The National Retail Federation (NRF) projected retail returns would reach $849.9 billion in 2025. It was also estimated that 19.3% of online sales would be returned. Returned products cannot go back on sale until staff inspect and restock them, so processing time affects availability.
In order to process returns faster, consider implementing the following tactics:
- Customer-initiated returns. An online portal records the request and alerts the team that inventory is coming back. Staff do not have to wait for an email exchange before processing begins.
- Barcode and RFID scanning. Staff members scan approved returns into the inventory system after inspection. Resellable products can then be marked as available.
- Cross-channel returns. Customers are allowed to return online orders to a store. After inspection, staff can add resellable products to that location’s available inventory.
A returned item does not contribute to product availability until it has been inspected, recorded, and restocked. Shorter processing times put resellable inventory back on sale sooner.
What to do when a product is out of stock
A stockout does not always mean the product is unavailable everywhere. Start by checking other locations and channels before changing the listing. If no sellable inventory remains, use the expected restock date to decide whether to take orders or collect notification requests.
Check other locations and fulfillment options
Review the product’s “Available” quantity at each location. From there, online shoppers can choose to pick up their order from another store when pickup in store is enabled there.
For customers shopping in person, Shopify POS Pro supports pickup orders at another eligible location. Staff can also use Ship to Customer at the register. Shopify assigns the order according to available inventory and the store’s routing rules.
Unified inventory also keeps the availability shown on different sales channels consistent.
“Before the migration, our inventory wasn’t unified, which undermined the value of store pickup. We were so grateful that Shopify solved that for us,” says Jennifer Devlin, owner of Salt Boutique. “Now, the product availability shoppers see online and on social media is always accurate. We’re maximizing exposure for our bestselling items, and can sell inventory from every location, which is huge.”
Take back orders or preorders
Use back orders when an existing product is scheduled to restock. Select “Continue selling when out of stock” for the product or variant in the Shopify admin. Customers can then place an order after the available quantity reaches zero, and the order remains unfulfilled until inventory arrives. Make sure to state the expected shipping date before checkout.
You can also update several products at once by adding the “Continue selling when out of stock column” to Shopify’s bulk editor. Preorders apply to products that have not been released yet. Shopify requires you to use a preorder app from the Shopify App Store, which manages the preorder terms and payment schedule.
Hearth Display uses limited preorder drops to inform the size of each production run.
“Right now, our current model is that we have a pre-order limited drop where customers can purchase Hearth Display until we sell through the production run in its entirety,” says Susie Harrison, cofounder and CGO at Hearth Display. “Then we actually head to production, produce those units, get those units delivered, and then we repeat the process with another limited drop for our next production run.”
Offer restock notifications
Some customers prefer to wait for inventory before placing an order. In that instance, you can use a stock alert app to collect their contact details and send them a notification when the product they’re looking for becomes available. Be sure to keep the product page published so customers can request an alert; the notification they receive should link back to the specific product or variant.
Update the product listing
It’s a good idea to keep a temporarily unavailable product visible in order to allow customers to place a back order, preorder it, or request a restock alert. If a product has been permanently discontinued, you should remove it from the channels where it is no longer sold.
Shopify makes this easy, allowing you to change product availability by sales channel. A product can remain available online and in the Shop app after you remove it from another channel. Shopify also supports hiding out-of-stock products from collections.
Improve inventory management with Shopify
Shopify keeps online and in-person inventory in the same system. A sale, return, or transfer updates the quantity assigned to that location. Shopify POS users said they saved 10 or more hours per month on inventory management.
Shopify inventory tools cover three parts of product availability:
- Inventory updates. Shopify POS and the online store use the same inventory record, so purchases and returns update the quantity at the location where they occur.
- Inventory across locations. Retailers can view stock held at retail stores, warehouses, pop-ups, and other fulfillment locations. Store staff can check another location and offer pickup or shipping when the item is unavailable locally.
- Low-stock alerts. Shopify Flow can send a notification when inventory falls below a set quantity. Sales and inventory reports provide the data used to set reorder points.
Shopify’s Winter ’26 operations updates added even more control over inventory transfers, allowing stores to now add, remove, or adjust items after a shipment is in transit or received. Shopify also expanded its inventory adjustment reports beyond the previous 180-day limit, and the reports now track changes by both SKU and location.
Product availability FAQ
What is meant by product availability?
Product availability refers to whether a particular item is in stock and accessible for customers to purchase when they want it. It ensures that supply meets demand and helps retailers meet customer expectations at the point of purchase, whether shoppers are browsing in a physical store, ordering online, or checking inventory through other sales channels.
How is product availability measured?
Product availability is measured using three complementary metrics:
- Stockout rate. Shows how often customers can’t complete purchases because products are out of stock.
- On-shelf availability (OSA). Measures whether products physically present in stores are actually accessible to customers on sales floors.
- Inventory turnover. Indicates how efficiently you convert inventory investments into sales by tracking how many times you sell and replace stock.
How do you ensure product availability?
To manage stock availability, follow these inventory management strategies:
- Monitor key availability metrics to identify problems before they cause stockouts.
- Use an inventory-management system that provides real-time visibility across all sales channels.
- Conduct regular audits to catch discrepancies between recorded and actual stock levels.
- Implement demand-based forecasting to align inventory with customer buying patterns.
- Maintain strong supplier relationships that provide support during challenges.
- Configure automated reordering to eliminate timing guesswork.
- Streamline the product returns process to restore inventory availability quickly.
How does product availability affect a retailer?
Product availability affects sales, customer trust, and inventory costs. Stockouts lead to missed purchases, and excess inventory ties up capital and raises carrying costs.
What should retailers do when a product is out of stock?
Check inventory at other locations and offer pickup or shipping. If a restock date is known, accept a back order or preorder and clearly state the expected delivery date. Otherwise, offer a restock alert or remove the listing if the product is discontinued.
