Inventory Forecasting and Restock Planning for Amazon 2026
TL;DR
Inventory forecasting and restock planning for Amazon is the process of predicting how fast your products will sell and timing purchase orders so you never run out or overstock. Getting it wrong costs you through BSR decay, storage fees, capacity restrictions, and wasted ad spend. This glossary covers every term you need to know, from sales velocity and reorder points to IPI scores and the 2026 fee changes, with formulas, benchmarks, and real practitioner insights.
Inventory mistakes are the quietest margin killer in ecommerce. Research suggests that mismanaging stock can slash EBITDA by 15 to 25 percent through a combination of unnecessary storage fees, lost sales during stockouts, and advertising waste. Yet most Amazon sellers treat inventory as an operations problem separate from marketing and finance. It isn’t.
Inventory forecasting and restock planning for Amazon ties together two related disciplines. Forecasting predicts how many units you’ll sell over a given period. Restock planning converts that prediction into purchase orders, shipment timing, and warehouse allocation. On Amazon specifically, the stakes are higher than on any other platform because the marketplace actively penalizes both understocking (through BSR loss, low-inventory fees, and suppressed listings) and overstocking (through aged inventory surcharges and IPI score drops).
This glossary gives you every term you’ll encounter in Seller Central, inventory tools, and agency conversations. Each entry includes a plain definition, the formula or benchmark where relevant, and the Amazon-specific consequences of getting it wrong. You can skim to the term you need or read straight through as an operating framework.
For the full operational playbook, see our inventory planning complete guide.
Demand Forecasting Terms
Sales Velocity
The number of units you sell per day (or per week) for a given SKU. Calculate it by dividing total units sold by the number of days in your measurement window.
A shorter window like 7 or 14 days reflects recent demand trends. A longer window of 30 or 60 days smooths out noise. Most sellers use both, comparing short-term velocity against long-term averages to spot acceleration or deceleration early.
Why it matters on Amazon: Sales velocity is the foundation of every other calculation in this glossary. Get this number wrong, and your reorder point, safety stock, and days of supply will all be off.
Practitioner warning: If your product was out of stock during the measurement window, the velocity calculation will understate true demand. Practitioners on Seller Central forums consistently flag this as one of the most common restocking mistakes. You need to either exclude stockout days from the denominator or use pre-stockout velocity as your baseline.
Related terms: Days of Supply, Reorder Point
Weighted Moving Average
A forecasting method that gives more weight to recent sales data and less weight to older data. Unlike a simple average that treats every week equally, a weighted moving average might assign 40% importance to the last two weeks, 30% to weeks three and four, and 30% to weeks five through eight.
This approach catches demand shifts faster while still providing enough historical smoothing to avoid overreacting to a single good or bad week.
In practice: Sellers who forecast weekly instead of monthly reduce stockout rates by 30 to 40 percent. The combination of weighted averages and weekly cadence is the simplest upgrade most sellers can make to their forecasting accuracy.
Related terms: Sales Velocity, Seasonal Decomposition
Seasonal Decomposition / Seasonality
The process of identifying recurring demand patterns tied to time of year, holidays, or cultural events. On Amazon, seasonality is pronounced. According to Amazon’s own 2024 holiday recap, FBA order volume during Black Friday and Cyber Monday week was 3.2 times the average weekly volume from the prior 90 days.
Seasonal decomposition means isolating that predictable spike (or dip) from your baseline demand, then building it into your forecast as a multiplier rather than relying on raw historical averages.
Amazon context: Q4 preparation needs to start in August or September for most China-sourced products because total lead time runs 45 to 90 days. If you wait until October to react to seasonal signals, the inventory won’t arrive in time. Plan your promotions and Buy Box protection around the same timeline.
Related terms: Lead Time, Safety Stock
Demand Forecasting (Baseline vs. Event-Driven)
Baseline forecasting predicts normal, everyday demand using historical sales data. Event-driven forecasting adds discrete adjustments for planned events: Lightning Deals, Prime Day, coupon launches, PPC budget increases, or seasonal promotions.
The distinction matters because treating a Lightning Deal like normal demand will corrupt your baseline. Amazon Lightning Deals typically increase unit velocity by 3 to 10 times during the deal window, which usually lasts 4 to 12 hours. A product selling 30 units per day might move 100 to 200 units during a single deal.
The fix: Model promotions as discrete events. After the event, strip those sales from your baseline calculation so future forecasts aren’t inflated. Similarly, strip out stockout periods so they don’t deflate your baseline.
PPC-Adjusted Forecasting
For many Amazon sellers, 30 to 60 percent of total sales come through Sponsored Products and Sponsored Brands advertising. This means changes to your PPC budget directly change your demand curve. If you increase ad spend by 40 percent, your demand forecast needs to reflect that planned change, not just react to it after the fact.
This is one of the biggest gaps in most sellers’ inventory forecasting and restock planning for Amazon. The advertising team and the operations team rarely coordinate. The result: ad campaigns drive demand spikes that the inventory plan wasn’t built for, leading to premature stockouts and wasted ad spend.
Related terms: Sales Velocity, Contribution Margin
ABC Analysis (Inventory Prioritization)
A tiering system that categorizes SKUs by revenue contribution:
- A items (top 20% of SKUs generating 80% of revenue): Forecast weekly, maintain higher safety stock, use air freight when needed.
- B items (next 30% of SKUs generating 15% of revenue): Forecast biweekly, moderate safety stock.
- C items (bottom 50% of SKUs generating 5% of revenue): Forecast monthly, minimal safety stock, strict aged-inventory guards.
Experienced practitioners recommend focusing forecasting effort on A items while being careful not to over-order C items. Over-ordering slow movers is how aged inventory surcharges accumulate.
Related terms: Contribution Margin, Aged Inventory Surcharge
Restock Planning and Order Timing Terms
Reorder Point (ROP)
The inventory level at which you need to place a new purchase order to avoid a stockout. This is the single most important number in restock planning.
Formula:
Reorder Point = (Average Daily Sales × Lead Time in Days) + Safety Stock
Worked example: If your forecast says 34 units per day, your total lead time is 28 days, and your safety stock covers 7 days:
ROP = (34 × 28) + (34 × 7) = 952 + 238 = 1,190 units
When your FBA inventory hits 1,190 units, place the order.
Amazon nuance: Lead time is the variable most sellers underestimate. It’s not just manufacturing time. It includes freight, customs clearance, and Amazon’s receiving window, which can add 3 to 14 or more days on its own. For a deeper walkthrough, see our guide on setting restock levels.
Related terms: Safety Stock, Lead Time, Days of Supply
Safety Stock
Extra inventory held as a buffer against demand spikes, supplier delays, or freight disruptions. Without safety stock, any deviation from your forecast results in a stockout.
Formula:
Safety Stock = (Max Daily Orders × Max Lead Time) – (Average Daily Orders × Average Lead Time)
General rule: If your lead time is unpredictable, or you’re heading into peak season, add a buffer of 20 to 30 percent to the reorder quantity beyond what the formula suggests.
Safety stock ties up cash, so there’s a real cost to holding too much. The goal is finding the minimum buffer that protects you against realistic worst-case scenarios, not theoretical ones.
Related terms: Reorder Point, Lead Time
Lead Time (Total: Supplier + Freight + FBA Receiving)
The total time from placing a purchase order to having inventory checked in and available for sale on Amazon. For most China-sourced products, this runs 45 to 90 days and includes:
- Supplier production: 15 to 30 days
- Freight (ocean): 20 to 40 days
- Customs and inland transit: 3 to 7 days
- Amazon FBA receiving: 3 to 14+ days
A forecasting tool that only factors in supplier lead time (step 1) will cause you to place purchase orders too late. Your system needs to account for the full pipeline.
Freight split framework for velocity tiers:
- High-velocity SKUs (>10 units/day): Air freight 30%, ocean 70%
- Medium-velocity SKUs (3 to 10 units/day): Air freight 15%, ocean 85%
- Low-velocity SKUs (<3 units/day): Ocean 100% with higher safety stock
Related terms: Reorder Point, Safety Stock
Days of Supply (DoS) / Days of Inventory (DOI)
How many days your current inventory will last at your current sell rate.
Formula:
Days of Supply = Units in FBA ÷ Average Daily Sales
If you have 200 units and sell 10 per day, you have 20 days of supply.
Target range: Below 14 days means stockout risk. Above 90 days means you’re tying up cash and paying unnecessary storage fees. Most products should sit in the 30 to 60 day range.
Amazon enforcement: As of 2026, the low-inventory-level fee kicks in below 35 days of supply for high-velocity products. So “just above 35” is the new floor for fast movers.
Related terms: Low-Inventory-Level Fee, Sales Velocity
Min/Max Restocking
An inventory model where stock is allowed to sell down to a minimum level, then replenished up to a maximum level. The cycle repeats continuously.
Setting these thresholds in days rather than units is recommended because unit-based targets don’t adjust for seasonal velocity changes. A “minimum of 500 units” means very different things in January versus November.
Shipment cadence guidelines:
- Fast movers: weekly or biweekly small shipments to keep DoS in target range and smooth capacity usage
- Slow movers: monthly shipments with strict aged-inventory monitoring
Related terms: Reorder Point, Days of Supply
Economic Order Quantity (EOQ)
The order size that minimizes total cost by balancing ordering costs (freight, handling, customs) against holding costs (storage fees, capital). Ordering too frequently wastes money on shipping. Ordering too infrequently creates overstock and storage fee exposure.
On Amazon, EOQ calculations need to factor in FBA storage fees, aged inventory surcharges, and capacity limits, not just traditional warehouse holding costs. A textbook EOQ that ignores Amazon’s fee structure will almost always suggest larger orders than what’s actually cost-optimal.
Related terms: Monthly Storage Fees, Aged Inventory Surcharge
Purchase Order (PO)
The formal order placed with your supplier specifying SKU, quantity, unit cost, delivery date, and shipping terms. In the context of Amazon inventory forecasting and restock planning, the PO is where the forecast becomes a commitment.
Timing the PO is straightforward once you have your reorder point calculated. The harder part is getting the quantity right, which requires balancing your demand forecast against capacity limits, storage costs, and cash flow constraints.
Amazon-Specific Metrics and Systems
Inventory Performance Index (IPI)
A score between 0 and 1,000 that Amazon assigns to your seller account measuring how efficiently you manage FBA inventory. While Amazon doesn’t publish its exact formula, the score is based on four factors:
- Excess inventory percentage
- Sell-through rate
- Stranded inventory percentage
- In-stock rate on popular ASINs
The 400 threshold is critical. If your IPI falls below 400, Amazon may limit how much inventory you can send in. Even if your product is selling well, you won’t be able to restock past a certain number of units.
2026 reality: The IPI threshold of 400 is still the line you don’t want to cross, but Amazon is enforcing it faster and harder than before. Fall below 400 at the wrong moment and you can see capacity cuts within days. Most experienced operators target 550 to 600 or higher because that range provides enough buffer to absorb seasonal swings.
If you’re struggling with account metrics, consider an Amazon account audit to identify the specific factors dragging your score down.
Related terms: FBA Capacity Limits, Sell-Through Rate, Stranded Inventory
Sell-Through Rate (STR)
Formula:
STR = Total Units Sold (last 90 days) ÷ Average Units Stored (last 90 days)
If you sold 300 units in 90 days and had an average of 100 units stored, your STR is 3.0. Amazon recommends keeping it above 2.0. STR is one of the four inputs to your IPI score, so it directly affects your storage capacity.
Related terms: IPI, Days of Supply
FBA Capacity Limits (2026 Update)
As of January 1, 2026, Amazon transitioned from its quarterly storage limit system to a more dynamic monthly capacity limit model. Capacity is now measured in cubic feet, not units.
Key changes:
- Storage allowances reduced from six months of forecasted sales to five months
- ASIN-level restock limits reactivated for individual SKUs
- Limits adjust monthly based on your IPI, sales forecast, and shipment history
Important nuance: During the May 2025 capacity reduction, even sellers with IPI scores above 550 experienced significant capacity decreases. High IPI provides better relative positioning but does not guarantee protection from system-wide cuts.
Related terms: IPI, Amazon Capacity Manager, AWD
Amazon Capacity Manager
A system within Seller Central that lets you request additional FBA storage space beyond your standard capacity limit. You submit a reservation fee (per cubic foot) that you’re willing to pay for the extra space. If Amazon grants the request and you generate enough sales to earn performance credits, the reservation fee can be offset partially or fully.
This is relatively new and most glossaries haven’t caught up. Think of it as a bidding system for FBA warehouse space. It’s most useful during Q4 when capacity is tightest and the cost of a stockout far exceeds the reservation fee.
Related terms: FBA Capacity Limits, Q4 Peak Season Surcharge
Amazon Warehousing and Distribution (AWD)
Amazon’s upstream bulk storage service. Units in AWD don’t count against your FBA storage volume or IPI calculations.
Strategy: Keep 60 to 90 days of stock in AWD and replenish FBA with 30-day batches. This improves both your IPI score and storage costs simultaneously because FBA only sees a month’s worth of inventory at a time.
AWD is particularly valuable for sellers who hit capacity limits frequently or who source large ocean freight shipments that would overwhelm their FBA allocation.
Related terms: FBA Capacity Limits, IPI, Monthly Storage Fees
FBA Restock Inventory Tool
Amazon’s built-in tool in Seller Central that provides restock recommendations. You input supply chain details (lead time, case pack quantity) and the tool suggests when and how much to send.
The catch: Practitioners on Seller Central forums consistently report that Amazon’s restock suggestions aren’t reliable. The algorithm often provides conservative estimates and doesn’t account for your specific lead times accurately. One seller noted that sorting inventory by Amazon’s estimated days-of-supply showed items flagged at 60 days remaining that actually needed restocking immediately based on recent sales velocity.
Best practice: Use Amazon’s restock recommendations as a secondary data point, not your primary planning tool. Cross-reference against your own velocity calculations and reorder point formulas.
Related terms: Reorder Point, Days of Supply
Stranded Inventory
FBA inventory that exists in Amazon’s warehouses but isn’t available for sale because the associated listing is suppressed, deleted, or otherwise inactive. Stranded inventory creates phantom “in-stock” counts that skew your velocity calculations and Days of Supply metrics.
You think you have 500 units available. But if 150 of those are stranded, your actual sellable inventory is 350, and your true Days of Supply is much lower than it appears. Meanwhile, the stranded units are still accruing storage fees.
Fix: Check the Stranded Inventory report in Seller Central weekly. Resolve listing issues immediately. If you need help with listing suppression and recovery, automated alerts can catch these before they distort your forecasting data.
Related terms: IPI, Monthly Storage Fees
Fee-Related Terms
Understanding Amazon’s fee structure is essential to inventory forecasting and restock planning for Amazon because fees penalize both extremes. Stock too little and you pay low-inventory fees. Stock too much and you pay aged inventory surcharges. The target zone is narrow, and it shifted in 2026.
Monthly Storage Fees
Amazon charges per-cubic-foot monthly fees for all inventory stored in FBA warehouses.
2026 rates:
- January through September: $0.78 per cubic foot per month (standard size)
- October through December (Q4): $2.40 per cubic foot per month (standard size)
Q4 rates are roughly three times higher than off-peak, which means overstock heading into the holidays is proportionally more expensive to hold.
Related terms: Days of Supply, EOQ
Aged Inventory Surcharge
A penalty fee assessed on inventory that has been sitting in FBA warehouses for extended periods, charged on top of regular monthly storage fees.
2026 tiers:
- 271 to 365 days (9 to 12 months): $0.30 per unit per month (increased from $0.15 in previous years)
- Over 365 days (12+ months): $0.35 per unit or $7.90 per cubic foot per month, whichever is greater
These surcharges are assessed monthly on the 15th. For a detailed breakdown of reduction strategies, see our guide on reducing aged inventory holding costs.
Bottom line: If you have 1,000 units of a product that hasn’t moved in over a year, you could be paying $350 or more per month in aged surcharges alone, before any other storage fees. This is why ABC analysis and aggressive clearance strategies for slow movers are non-negotiable.
Related terms: ABC Analysis, Overstock/Excess Inventory
Low-Inventory-Level Fee
A fee charged when your FBA stock falls below a minimum days-of-supply threshold for products with consistent sales history.
2026 update: The threshold was raised from 28 days to 35 days of forecasted demand. The fee ranges from $0.32 to $0.97 per unit depending on size tier.
This fee penalizes sellers who run too lean. Combined with the aged inventory surcharge that penalizes overstocking, Amazon is effectively squeezing sellers into a 35 to 90 day supply window. Inventory forecasting and restock planning for Amazon has never required more precision than it does now.
Related terms: Days of Supply, Safety Stock
Storage Utilization Surcharge
An additional fee that applies when your storage utilization ratio (cubic feet stored vs. cubic feet shipped) exceeds certain thresholds. This targets sellers who use FBA as a long-term warehouse rather than a fulfillment pipeline.
The fix is straightforward: keep inventory flowing through FBA at a healthy rate rather than letting it sit. AWD can serve as your bulk storage layer, with FBA receiving only what you’ll sell in the next 30 days.
Related terms: AWD, Sell-Through Rate
Q4 Peak Season Surcharge
The elevated storage fee rate that applies from October through December. At $2.40 per cubic foot (vs. $0.78 off-peak), Q4 storage is roughly 3x more expensive. This means inventory that you planned to sell during the holidays but didn’t will cost you significantly more to hold.
Plan shipment timing so Q4 inventory arrives close to when you need it, not months early. Stagger shipments using AWD as a buffer.
Performance and Consequence Terms
Best Seller Rank (BSR)
Amazon’s ranking of how well a product sells within its category, updated hourly. Lower numbers mean higher sales. BSR directly influences organic visibility, as Amazon’s algorithm surfaces products that are selling well.
BSR is the reason stockouts are so destructive. When sales stop, BSR decays within hours, and your product drops in search results. Competitors absorb your traffic. Your organic rank erodes, and the recovery period far exceeds the stockout duration.
Related terms: Stockout, BSR Recovery Period
Stockout
When your FBA inventory reaches zero units. On Amazon, the consequences cascade immediately:
- Sales drop to zero
- BSR starts decaying within hours
- Amazon suppresses your listing from search results
- Competitors absorb your organic traffic
- Keyword rankings deteriorate
- Advertising campaigns pause automatically
Stockouts last 7 to 10 days on average, causing roughly an 8-position drop in keyword rankings and significant revenue loss.
Real-world case: In November, one seller ran out of stock for just five days. Their BSR dropped from #180 to #740. Their ACOS jumped from 18% to 61%. Three weeks after restocking, keyword rankings still had not returned to pre-stockout levels.
A five-day stockout doesn’t cost five days of revenue. It costs weeks of depressed sales, elevated ad costs, and lost competitive position.
Related terms: BSR Recovery Period, FBM Backup Listing
BSR Recovery Period
The time needed to restore BSR to pre-stockout levels after inventory is replenished. Typical recovery takes 2 to 4 weeks of consistent sales.
More severe pattern: a two-week stockout can take two months to fully recover from. During that recovery period, organic traffic is depressed and competitors have filled the gap. You’re essentially re-launching the product.
This is why safety stock isn’t a luxury. The cost of carrying extra inventory is almost always less than the cost of a single significant stockout.
Related terms: Stockout, Safety Stock
Buy Box Eligibility
The Buy Box is the “Add to Cart” button on a product listing. Multiple sellers can list against the same ASIN, but only one holds the Buy Box at a time. Amazon considers pricing, fulfillment method (FBA preferred), account health, and stock availability when rotating the Buy Box.
Inventory connection: Going out of stock means losing the Buy Box entirely. Even after restocking, it can take time to regain Buy Box share, especially if competitors captured it during your absence.
Overstock / Excess Inventory
Inventory levels that exceed projected demand within a reasonable timeframe (typically 90 days). Excess inventory ties up working capital, lowers your IPI score, triggers aged inventory surcharges, and inflates storage costs.
Amazon flags excess inventory in Seller Central with recommended actions: create a sale, submit a removal order, or adjust pricing. Ignoring these recommendations compounds the problem.
FBM Backup Listing (Stockout Mitigation)
A Fulfilled by Merchant (FBM) offer on the same ASIN as your FBA listing. When FBA inventory hits zero, the FBM offer becomes the active listing, keeping the product available for purchase.
FBM fulfillment won’t maintain BSR as effectively as FBA (since FBA conversion rates are typically higher), but it prevents complete listing suppression and keeps some sales flowing. Think of it as an insurance policy, not a permanent strategy.
Practitioner tip: Set up FBM backup listings on your top 20% of SKUs (your A items from ABC analysis) before you actually need them. Having the listing active and ready to catch orders during an FBA gap can save weeks of recovery time.
Multi-Channel and Operational Terms
Inventory Sync (Amazon + Shopify/D2C)
Real-time synchronization of inventory counts across all sales channels. A sale on Shopify that isn’t reflected on Amazon fast enough can push your FBA stock count to zero and trigger an unplanned stockout.
Practitioners report that inventory accuracy and real-time stock visibility across channels is one of the most underrated factors in maintaining Amazon performance. If you sell on multiple platforms, integrating your inventory across channels isn’t optional. It’s a prerequisite for accurate forecasting.
Related terms: Multi-Channel Fulfillment, Stockout
3PL (Third-Party Logistics)
A third-party logistics provider that handles warehousing, picking, packing, and shipping on your behalf outside of Amazon’s fulfillment network. 3PLs are commonly used as overflow storage, FBM fulfillment centers, or staging areas for FBA shipments.
In an inventory forecasting and restock planning context, 3PLs add a step to your lead time calculation. You need to account for the time it takes to transfer inventory from 3PL to FBA, not just from supplier to 3PL.
Multi-Channel Fulfillment (MCF)
Amazon’s service that lets you use FBA inventory to fulfill orders from non-Amazon channels (Shopify, your own website, etc.). MCF simplifies operations by consolidating inventory into one pool but introduces a dependency on FBA capacity and can affect your Amazon-specific metrics if not managed carefully.
Brands that sell across Amazon and D2C channels need to decide whether to use MCF, a separate 3PL, or a hybrid approach. The right answer depends on order volume, margin targets, and how much control you want over the customer experience.
Contribution Margin (as a Restock Prioritization Lens)
Contribution margin is revenue minus all variable costs (COGS, fulfillment fees, advertising, referral fees). It tells you how much profit each unit actually generates.
Why this belongs in an inventory glossary: Not all SKUs deserve equal restocking priority. A product with $2 contribution margin and a product with $15 contribution margin shouldn’t get the same safety stock budget or air freight allocation. Prioritize restocking based on contribution margin, not just sales velocity.
No other ranking page for inventory forecasting and restock planning for Amazon connects margin analysis to restock priority, but it’s one of the most impactful decisions you can make. For a deeper breakdown, see our guide on contribution margin for ecommerce teams.
Related terms: ABC Analysis, EOQ
Putting It All Together: Weekly Monitoring Rhythm
Knowing the terms is step one. Applying them consistently is where results come from. Here’s a quick-reference checklist for weekly inventory governance:
Every week:
- Review Days of Supply for all A-tier SKUs. Flag anything below 35 days or above 75 days.
- Check stranded inventory report. Resolve immediately.
- Compare short-term velocity (7-day) to long-term velocity (30-day) for trend detection.
- Verify any SKUs approaching their reorder point. Trigger POs.
Every two weeks:
- Update velocity calculations for B-tier SKUs.
- Review IPI score trend. Investigate any movement toward 400.
- Check aged inventory report. Create removal or clearance plans for anything approaching 271 days.
Monthly:
- Full forecast refresh incorporating latest seasonality data, planned promotions, and PPC budget changes.
- Review FBA capacity limits and adjust shipment staging through AWD if needed.
- C-tier SKU review. Decide: restock, discount, or remove.
This cadence, combined with the terms and formulas in this glossary, gives you a working system for Amazon inventory forecasting and restock planning.
When DIY spreadsheets and manual checks start breaking down (usually around 50+ active SKUs or during rapid growth), it’s worth bringing in professional support. EZCommerce offers inventory depth planning, FBA fee audits, and aged inventory alerts as part of its Amazon management services.
Request a free brand audit to identify where your inventory process has gaps and get a 90-day action plan.
Frequently Asked Questions
What is inventory forecasting and restock planning for Amazon?
It’s the combined process of predicting future sales volume for your FBA products and timing purchase orders so inventory arrives before you stock out but doesn’t arrive so early that you incur excessive storage fees. It requires understanding your sales velocity, lead times, safety stock needs, and Amazon’s capacity and fee systems.
How do I calculate my reorder point for Amazon FBA?
Use this formula: Reorder Point = (Average Daily Sales × Total Lead Time in Days) + Safety Stock. Make sure “total lead time” includes manufacturing, freight, customs, and FBA receiving time, not just supplier production time. For China-sourced products, total lead time typically runs 45 to 90 days.
What IPI score should I target?
The minimum threshold is 400. Drop below that and Amazon can restrict your storage capacity within days. Most experienced sellers target 550 to 600 or higher to maintain a comfortable buffer against seasonal fluctuations and system-wide capacity adjustments.
How much safety stock should I keep?
Calculate it using: Safety Stock = (Max Daily Orders × Max Lead Time) minus (Average Daily Orders × Average Lead Time). If your supply chain is unpredictable or you’re heading into peak season, add a 20 to 30 percent buffer on top. The cost of carrying extra stock is almost always less than the cost of a stockout.
What happens to my BSR when I stock out?
BSR begins decaying within hours of going out of stock. Amazon suppresses your listing from search results, competitors absorb your traffic, keyword rankings deteriorate, and ad campaigns pause. Recovery typically takes 2 to 4 weeks, and a two-week stockout can require two months of recovery.
What’s the difference between Amazon’s Restock Tool recommendations and my own calculations?
Amazon’s FBA Restock Inventory Tool provides suggestions based on its own demand estimates, but sellers widely report that these recommendations are often conservative and inaccurate. The tool frequently doesn’t account for your specific lead times or recent velocity changes. Use it as a secondary reference, not your primary planning method.
What are the 2026 aged inventory surcharge rates?
For inventory aged 271 to 365 days, the surcharge is $0.30 per unit per month. For inventory over 365 days, it’s $0.35 per unit or $7.90 per cubic foot per month (whichever is greater). These are assessed monthly on the 15th and stack on top of regular storage fees.
How does multi-channel selling affect Amazon inventory planning?
If you sell on both Amazon and another platform like Shopify, a sale on your D2C site that isn’t synced to Amazon quickly enough can push your FBA count to zero and trigger an unplanned stockout. Real-time inventory synchronization across channels is essential for accurate forecasting and uninterrupted Amazon performance.