Instock percentage is the metric Walmart buyers watch more closely than almost anything else. It answers a simple question: when a customer walks into a store (or goes to walmart.com) to buy your product, is it actually on the shelf?
A high instock percentage means you're capturing demand. A low one means you're leaving money on the table — and your buyer knows it.
The good news is that instock is largely within your control. Not entirely, but more than most suppliers realize. The key is diagnosing where and why instock is falling, then addressing the specific root cause rather than applying generic fixes.
What Instock Percentage Actually Measures
Walmart calculates instock at the item-store level. An item is "in stock" at a store if the store has a positive on-hand quantity. The instock percentage is the share of item-store combinations that have product available, out of all item-store combinations where the item is authorized (valid).
So if you have 100 items authorized across 4,000 stores (400,000 item-store combinations), and 380,000 of them have product on the shelf, your instock is 95%.
Important nuances:
- It's binary. Having 1 unit or 1,000 units both count as "in stock." Having 0 units counts as out of stock regardless of whether a shipment is arriving tomorrow.
- It's based on valid stores. Stores where the item isn't authorized don't count against you.
- Store and eComm are separate. Your brick-and-mortar instock and your online instock are tracked independently.
The 6 Root Causes of Low Instock
When your instock drops, the natural reaction is to "ship more product." But instock problems have specific causes, and the fix depends on the diagnosis.
1. DC Ordering Gaps
The distribution center isn't placing orders for your items, even though stores need product. This is the most common — and most insidious — cause of instock problems because it's invisible at the store level. Stores run out, but the root cause is upstream.
How to diagnose: Cross-reference your DC Metrics data with Order Forecast. If stores have demand but the DC shows no pending orders, you have an ordering gap.
How to fix: Bring specific DC-level data to your buyer. Request a replenishment review at the affected DC. Check for manual holds, excess inventory flags, or forecast misalignment.
2. Forecast Too Low
Walmart's replenishment system orders based on demand forecasts. If the forecast for your items is lower than actual demand, the system won't order enough product — and stores run out before the next replenishment cycle.
How to diagnose: Compare your Store Demand Forecast to actual sales from Sales & Inventory. If actual sales consistently exceed the forecast by 15% or more, the forecast is too conservative.
How to fix: Work with your buyer to adjust the forecast baseline. Provide sell-through data from promotional periods to demonstrate actual demand levels. For seasonal items, request forecast overrides ahead of the season.
3. Store Backroom Issues
Product is in the store — just not on the shelf. It's sitting in the backroom because the shelf is plugged with another item, the shelf label is missing, or the overnight stocking crew didn't get to your category.
How to diagnose: This one is harder to see in Scintilla data. Look for stores where on-hand quantity is positive but sales are zero or near-zero for consecutive weeks. Product is there, but it's not selling — which often means it's not actually on the shelf.
How to fix: Backroom issues are largely outside your direct control, but you can flag specific stores to your buyer and request a store-level inventory audit. Third-party retail service teams can also help ensure shelf compliance.
4. Modular/Planogram Changes
When Walmart resets a category — changing the planogram (shelf layout) — items can temporarily lose their shelf position. If the transition isn't smooth, product that was on the shelf gets pulled to the backroom and may not get reset for days or weeks.
How to diagnose: Check your Modular Plan Metrics data for recent modular changes. If instock drops coincide with a modular reset, the transition is the likely cause.
How to fix: Coordinate with your buyer ahead of modular resets. Ensure adequate inventory is staged at the DC before the reset date. Follow up after the reset to confirm items are back on the shelf.
5. Supplier Fulfillment Problems
Sometimes the problem is on your side. If your fill rate is low — meaning you can't fulfill the full quantity Walmart orders — stores will go out of stock because they're not getting what was ordered.
How to diagnose: Check your Vendor Scorecard for OTIF (On Time In Full) metrics and fill rate. Also look at Tender Analysis — compare ordered quantities to shipped quantities.
How to fix: This requires operational improvements on your end: production planning, inventory management, transportation reliability. Work with your logistics team to identify which items and which DCs have the lowest fill rates and prioritize those.
6. Seasonal Demand Spikes
Predictable demand spikes — back to school, holidays, spring season — can cause temporary instock drops if you haven't built inventory ahead of the demand curve.
How to diagnose: Compare current week instock to the same fiscal week last year. If the same pattern occurred last year, it's a seasonal issue.
How to fix: Build pre-season inventory at the DC level. Use last year's weekly sales pattern to time inventory builds. Discuss seasonal inventory targets with your buyer 4-6 weeks before the expected demand increase.
A Practical Instock Improvement Process
Here's a systematic approach you can implement with your weekly Scintilla data:
Step 1: Identify Your Worst Performers
Each week, rank your items by instock percentage. Focus on the bottom 10% — these are the items dragging your overall number down. Often, fixing 5-10 items can move your aggregate instock by a full percentage point.
Step 2: Segment by Root Cause
For each low-instock item, determine the root cause using the diagnostic methods above:
- Is the DC ordering? (DC Metrics + Order Forecast)
- Is the forecast accurate? (Demand Forecast vs. actual sales)
- Is it a fulfillment issue? (Scorecard OTIF + fill rate)
- Is there a modular change? (Modular Plan Metrics)
Step 3: Prioritize by Sales Impact
Not all instock gaps are equal. A 90% instock on a $50K/week item costs you $5K in potential sales. A 90% instock on a $500/week item costs you $50. Focus your effort where the sales impact is highest.
Step 4: Take Action With Data
When you contact your buyer about an instock issue, come with specifics:
- Which items are affected
- Which DCs or stores are the problem
- What the root cause appears to be
- What the estimated sales impact is
- What you're asking them to do
Buyers deal with dozens of suppliers. The ones who show up with clear, data-backed requests get action. The ones who say "our instock is low, can you look into it?" get put at the bottom of the pile.
Step 5: Track Week Over Week
Instock improvement isn't a one-time fix. Track your instock at the item level every week. Monitor whether the actions you took last week are showing results this week. Celebrate the wins — even a 0.5% improvement across your portfolio represents real recovered sales.
What "Good" Looks Like
Instock benchmarks vary by category, but general guidelines for Walmart suppliers:
- 97%+ — Excellent. You're capturing nearly all available demand.
- 95-97% — Good. There's room to improve, but you're in a solid position.
- 90-95% — Needs attention. You're likely leaving significant sales on the table.
- Below 90% — Critical. This will come up in buyer meetings and could impact your shelf space.
For eCommerce instock, the bar is even higher. Online shoppers have zero tolerance for out-of-stocks — they'll simply buy from another seller or another brand. Target 98%+ for online items.
The Compound Effect
Here's what makes instock improvement so powerful: it compounds. Higher instock means more sales. More sales means better demand signals. Better demand signals mean more accurate forecasts. More accurate forecasts mean better replenishment. Better replenishment means higher instock.
The opposite is also true — low instock creates a downward spiral where poor sales data leads to lower forecasts, which leads to less ordering, which leads to even lower instock.
Breaking the negative cycle and establishing the positive one is one of the highest-leverage things you can do as a Walmart supplier. And it starts with reading your data every week.