Top 5 Common FBA Errors Costing Amazon Sellers Money

TL;DR

• Amazon may miscalculate dimensions, leading to higher fulfillment and storage fees. Always verify.

• Lost or damaged inventory isn’t always reimbursed. Regularly check and file claims for missing stock.

• High storage fees add up fast. Monitor inventory age and remove slow-moving stock before fees increase.

• Incorrect labeling or packaging can cause delays and extra charges. Follow Amazon’s prep guidelines.

• Stranded and suppressed listings stop sales. Check and fix inactive listings to keep inventory moving.

If you're selling on Amazon, you know how quickly small mistakes can eat into your profits. Amazon's FBA (Fulfillment by Amazon) program is designed to make selling easier, but it comes with its own set of rules, fees, and fine print. The problem? Many sellers unknowingly make costly errors that drain their margins.

From misplaced inventory to overlooked reimbursements, these mistakes can add up to thousands of dollars in lost revenue each year. The good news? Most of these errors are fixable—if you know what to look for.

Let’s look into the top five most common FBA mistakes that could be costing you money and, more importantly, how to avoid them.

Quick guide

• #1: Inaccurate FBA fee charges

• #2: Lost or damaged inventory without reimbursement

• #3: Overpaying for Amazon storage fees

• #4: Improper labeling and prep issues

• #5: Failure to monitor stranded and suppressed listings
  
  

#1: Inaccurate FBA fee charges

Amazon charges FBA sellers for storage, fulfillment, and other services based on product dimensions and weight. However, Amazon doesn’t always get these measurements right. If your product is incorrectly classified—whether in terms of size, weight, or category—you could be paying higher fulfillment and storage fees than necessary.

How this happens

• Incorrect product dimensions – Amazon's system might mismeasure your product, placing it in a higher (and more expensive) tier.

• Wrong weight category – If your product is weighed incorrectly, you may be charged more for shipping and fulfillment.

• Misclassified as an oversized item – Oversized items incur significantly higher fees. If Amazon wrongly categorizes a standard-size item as oversized, your costs will shoot up.

Why does this cost you money?

FBA fees are deducted automatically, and unless you actively check, you might not even realize you're overpaying. A few cents per unit may not seem like much, but over hundreds or thousands of sales, this can add up to hundreds or even thousands of dollars in unnecessary fees.

How to fix this

• Check Amazon’s measurements – Go to Manage inventory > Edit > More details and compare the listed dimensions with your actual product size and weight.

• Weigh and measure your products yourself – Use a scale and measuring tape to verify the correct values.

• Request a remeasurement – If you find discrepancies, open a case with seller support and request an FBA fee review. Amazon will remeasure your product and adjust the fees if an error is found.

• Monitor fees regularly – Even if your product was correctly measured before, Amazon occasionally updates its dimensions, so check back periodically.

By keeping an eye on FBA fees and ensuring accurate product measurements, you can prevent unnecessary charges and keep more of your profits.

#2: Lost or damaged inventory without reimbursement

When you send your inventory to an Amazon fulfillment center, you trust that it will be stored and handled properly. However, mistakes happen, and products can be lost, damaged, or mishandled during storage or fulfillment. If Amazon is responsible for the damage or loss, they are supposed to reimburse you—but many sellers don’t realize they need to track these issues themselves.

How this happens

• Lost during inbound shipments – Your shipment arrives at an Amazon warehouse, but some units mysteriously go missing.

• Damaged in Amazon’s warehouse – Products get crushed, broken, or rendered unsellable due to mishandling.

• Lost after check-in – Items that were received successfully somehow disappear from inventory.

• Wrong Amazon FBA inventory reimbursements – Amazon may acknowledge the loss or damage but refund you an incorrect amount or not refund you at all.

Why does this cost you money?

If you don’t regularly audit your inventory, you might never realize when units are lost or damaged. Amazon won’t always notify you or automatically issue reimbursements, meaning you could be losing thousands of dollars in missing inventory without even knowing.

How to fix this

• Regularly check your inventory reports – Go to Reports > Fulfillment > Inventory adjustments to track lost or damaged items. Use the Reimbursements report to see if Amazon has refunded you for missing inventory.

• Track your inbound shipments – Go to Manage FBA shipments and check if the number of received units matches what you sent. If there’s a discrepancy, file a claim within 9 months of shipment.

• Manually request reimbursements – If you notice lost or damaged units that haven’t been reimbursed, open a case with seller support and provide the details. Amazon will investigate and either return your products or issue a reimbursement based on the estimated sale price.

• Use a reimbursement tool or service – If you manage a high volume of sales, using third-party Amazon seller reimbursement services can help track these errors automatically.

By staying on top of lost and damaged inventory, you can recover money that rightfully belongs to you and ensure your profits aren’t quietly disappearing.

#3: Overpaying for Amazon storage fees

Amazon charges monthly storage fees and long-term storage fees for products sitting in their warehouses. If you don’t keep track of your inventory levels, you could be spending way more than necessary on storage, cutting into your profits.

How this happens

• Slow-moving inventory – Products that aren’t selling fast enough pile up in FBA warehouses, leading to higher monthly storage fees.

• Long-term storage fees – If inventory sits for over 181 days, Amazon starts charging aged inventory surcharges, which are significantly higher.

• Improper inventory forecasting – Ordering too much stock at once means you pay extra to store it before it even sells.

• Mismanaged stranded inventory – If a listing is suppressed or inactive, your products remain in storage but aren’t available for purchase—costing you money with no return.

Why does this cost you money?

Amazon’s storage fees have increased sharply over time. During peak seasons (October to December), storage fees almost triple. If you don’t monitor your inventory, you could end up spending more on storage than you make in sales.

How to fix this

• Monitor your inventory age reports – Go to Reports > Fulfillment > Inventory age to see which items are at risk of long-term storage fees. Prioritize selling older inventory before Amazon starts charging higher fees.

• Set up automatic removals – In FBA settings, enable automatic removal of unsold stock to avoid long-term storage fees. Amazon can send inventory back to you or dispose of it at a lower cost than keeping it in storage.

• Use Amazon’s FBA liquidation program – Instead of paying storage fees, liquidate slow-moving inventory and recover some of your costs.

• Keep an eye on stranded inventory – Check Manage inventory > Fix stranded inventory to make sure your products are available for sale.

• Improve demand forecasting – Use historical sales data and tools like Amazon’s Inventory Performance Dashboard to order the right amount of stock at the right time.

By managing your storage wisely, you can cut unnecessary fees, free up cash flow, and maximize your profits instead of letting Amazon’s warehouses drain your money.

#4: Improper labeling and prep issues

Amazon has strict requirements for labeling and prepping FBA inventory. If you don’t follow these rules, your shipments can be delayed, rejected, or even incur additional fees because Amazon will have to fix the mistakes for you.

How this happens

• Missing or incorrect barcodes – Every unit needs an FNSKU barcode (or manufacturer barcode if you use stickerless commingling). If barcodes are smudged, unreadable, or missing, Amazon will either charge you a per-unit labeling fee or reject the inventory.

• Poor packaging – Certain products (like fragile items, liquids, or textiles) need bubble wrap, poly bags, or suffocation warning labels. If you don’t follow these guidelines, Amazon may repackage the items for a fee or deem them unfulfillable.

• Mixing SKUs in a single box – If multiple ASINs are packed together without clear separation, Amazon can miscount inventory or send the wrong items to customers, leading to more returns, bad reviews, and lost sales.

• Ignoring box content requirements – Not providing box-level details in shipments (like unit count and weight) can result in delays and non-compliance fees.

Why does this cost you money?

Improper labeling and prep issues lead to:

• Amazon charges you for extra work (per-unit labeling, repackaging, or manual processing fees).

• Delayed inventory check-in, which means products aren’t available for sale when needed.

• Rejected or lost shipments, forcing you to reship at your own cost.

• Higher return rates from customers receiving incorrect or damaged products.

How to fix this

• Follow Amazon’s prep and labeling requirements – Check Amazon’s FBA packaging and prep guide to understand what each product type requires. If using Amazon barcode labeling, make sure each unit has a clear, scannable FNSKU.

• Use Amazon’s FBA Label Service (if needed) – If you don’t want to label products yourself, Amazon can do it for you for a small per-unit fee (but doing it yourself saves money).

• Double-check shipments before sending – Ensure all barcodes are correct and boxes contain the right SKUs before shipping. Provide box-level details in Seller Central > Send to Amazon to avoid non-compliance fees.

• Use a prep service (if necessary) – If you have high inventory turnover, an FBA prep center can handle labeling and packaging correctly before items reach Amazon.

By properly labeling and preparing your inventory, you avoid unnecessary fees, speed up check-in times, and ensure customers receive the right products—leading to better sales and fewer issues.

#5: Failure to monitor stranded and suppressed listings

Amazon sellers often assume that once their products are in the FBA warehouse, they are automatically available for sale. However, listings can become stranded or suppressed, meaning they are no longer visible to customers—and if your products aren’t live, you’re not making any sales.

How this happens

• Stranded inventory – Your products are sitting in Amazon’s warehouse, but they aren’t linked to an active listing due to issues like:

  • Listing deactivation (e.g., policy violations, missing details, or expired approvals).

  • ASIN merge errors (Amazon combines your ASIN with another, making your listing unavailable).

  • FBA SKU errors (Amazon disconnects inventory from the listing, making it unfulfillable).

• Suppressed listings – Amazon removes your product from search results if it fails to meet listing quality standards. Common reasons include:

  • Missing or incorrect images (especially the main image).

  • Inaccurate product information (title too long, missing bullet points, or vague descriptions).

  • Pricing errors (your product is priced too high or too low compared to Amazon’s internal pricing rules).

Why does this cost you money?

• You lose potential sales – If customers can’t see your product, they can’t buy it.

• Amazon still charges storage fees – Your inventory is stuck in the warehouse, accumulating storage costs.

• Stranded inventory can be disposed of – If left unresolved for too long, Amazon may automatically remove or liquidate stranded inventory, leading to total loss.

How to fix this

• Regularly check the stranded inventory report – Go to Inventory > Fix stranded inventory in Seller Central. Identify and relist any stranded products immediately.

• Resolve suppressed listings quickly – Go to Manage inventory > Suppressed listings and check for missing details or errors. Update images, titles, and pricing as required.

• Keep an eye on pricing rules – If Amazon flags your product as having an uncompetitive price, adjust it manually or enable Automated Pricing to stay compliant.

• Fix listing quality issues before they cause suppression – Ensure your titles, bullet points, and descriptions follow Amazon’s style guide. Always upload high-quality images that meet Amazon’s image requirements.

By monitoring stranded and suppressed listings regularly, you can keep your products active, maximize visibility, and prevent lost sales—ensuring your inventory is making you money instead of sitting idle in a warehouse.

Staying on top of these common FBA errors can save you thousands of dollars in unnecessary fees, lost inventory, and missed sales. But let’s be honest—manually tracking every mistake Amazon makes can be time-consuming. Amazon FBA reimbursement services like Refunzo can make things easier.

With automated tracking and expert audits, Refunzo helps Amazon sellers recover lost money from incorrect FBA charges, missing reimbursements, and inventory mishaps. Instead of letting Amazon quietly eat into your profits, let Refunzo help you get back what you’re owed.