Fee Audit
Audit Amazon's fees for overcharges, detect referral fee errors, FBA fulfillment miscalculations, wrong category assignments, and weight/dimension discrepancies.
Difficulty: 🟡 Intermediate · Reading time: ~15 min
📋 Overview
Amazon charges dozens of different fees across referral fees, FBA fulfillment fees, closing fees, and more. Mistakes happen, products may be assigned the wrong category, dimensions may be recorded incorrectly, or fee tiers may be applied in error. The Fee Audit tool scans your account for these overcharges and helps you recover the difference.
The hidden cost of fee errors: Studies show that 1-3% of Amazon FBA fees contain errors that result in seller overcharges. For a seller paying EUR 100,000/year in Amazon fees, that is EUR 1,000 to EUR 3,000 in unnecessary costs. Fee Audit finds and helps you recover these overcharges automatically.
📊 Key Performance Indicators
Total Issues
Count and total value of detected overcharges
Action Needed
Issues ready for claim filing
Claims Filed
Claims submitted to Amazon
Resolved
Amount successfully recovered
Quick win: Focus on the "Action Needed" KPI first. These are verified overcharges with the highest confidence level, ready for you to claim immediately.
ROI / Impact Calculator
Use these benchmarks to estimate what fee errors might be costing you:
EUR 25,000
1-3%
EUR 250 - EUR 750
EUR 50,000
1-3%
EUR 500 - EUR 1,500
EUR 100,000
1-3%
EUR 1,000 - EUR 3,000
EUR 250,000
1-3%
EUR 2,500 - EUR 7,500
EUR 500,000
1-3%
EUR 5,000 - EUR 15,000
EUR 1,000,000
1-3%
EUR 10,000 - EUR 30,000
Real-world example: A kitchen products seller discovered that 23 of their ASINs were classified in the wrong fee category ("Home & Garden" instead of "Kitchen"), resulting in a 2% higher referral fee on each sale. Over 8 months and 14,000 units sold, the total overcharge was EUR 4,200. They recovered the full amount through SellerMagnet's claim process.
📈 Charts
Overcharge by Fee Type (Bar Chart): Breakdown showing which fee categories have the most overcharges (Referral Fee, FBA Fulfillment, Closing Fee, Category Error, Weight/Dimension)
Issue Distribution (Pie Chart): Visual breakdown of issue types
Best practice: If the bar chart shows a disproportionate amount of overcharges in "Weight/Dimension," it likely means Amazon's recorded product dimensions are wrong for multiple ASINs. Consider submitting a batch cubiscan request to correct them all at once.
Audit Types
Referral Fee
Amazon charged a higher referral percentage than expected
Wrong product category assignment
FBA Fulfillment Fee
Incorrect fulfillment fee based on weight or dimensions
Incorrect recorded weight/dimensions
Closing Fee
Incorrect closing fee charged
Media vs. non-media classification error
Wrong Category
Product assigned to wrong category affecting fee rates
Amazon auto-categorization mistake
Weight / Dimension
Amazon's recorded weight or dimensions do not match actual
Measurement error during first FBA check-in
👣 Step-by-Step Example: Detecting a Weight/Dimension Overcharge
Scenario: You sell a premium phone case (ASIN: B09CASE001). The actual product weight is 120g and the package dimensions are 18 x 10 x 2 cm. However, Amazon has recorded the weight as 450g and dimensions as 22 x 15 x 8 cm, likely because the system picked up measurements from a different product or a packaging error during check-in.
Impact:
FBA Fulfillment Fee
EUR 2.77 (Small Standard)
EUR 4.49 (Large Standard)
EUR 1.72/unit
Monthly units sold
400
400
---
Monthly overcharge
---
---
EUR 688.00
Annual overcharge
---
---
EUR 8,256.00
What SellerMagnet shows:
Audit Type
Weight / Dimension
Actual Fee
EUR 4.49
Expected Fee
EUR 2.77
Overcharge / Unit
EUR 1.72
Occurrences (last 90 days)
1,200
Total Overcharge
EUR 2,064.00
Status
Action Needed
Steps to resolve:
Click File Claim on the row.
In the notes, include: "Product actual weight is 120g, actual dimensions 18x10x2cm. Amazon has recorded 450g and 22x15x8cm. Request cubiscan remeasurement."
Submit the claim.
Separately, log into Seller Central and open a case requesting a cubiscan for this ASIN (Amazon Standard Identification Number) to permanently correct the dimensions.
Once corrected, all future orders will be charged the correct fee.
Critical: Weight/dimension errors are the most expensive fee error type because they affect EVERY unit sold. A EUR 1.72/unit overcharge on a product selling 400 units/month costs you EUR 8,256/year. Prioritize these claims above all others.
👣 Step-by-Step Example: Wrong Category Assignment
Scenario: Your stainless steel water bottle (ASIN: B09BOTTLE1) is categorized under "Sports & Outdoors" (15% referral fee) instead of "Kitchen & Dining" (8% referral fee). The product sells for EUR 29.99.
Referral Fee
EUR 2.40 (8%)
EUR 4.50 (15%)
EUR 2.10/unit
Monthly units sold
250
250
---
Monthly overcharge
---
---
EUR 525.00
Annual overcharge
---
---
EUR 6,300.00
Category errors compound silently. Unlike a one-time lost shipment, a wrong category assignment overcharges you on every single sale until it is corrected. Even a 1-2% difference in referral fee rates adds up to thousands of euros per year on a moderate seller.
Audit Items Table
Checkbox
Select for bulk actions
Marketplace
Country flag
Audit Type
Fee type badge
Product
Product name
ASIN
Amazon Standard Identification Number
SKU (Stock Keeping Unit)
Seller SKU
Actual Fee
What Amazon charged
Expected Fee
What the fee should have been (calculated)
Overcharge / Unit
Per-unit overcharge amount
Occurrences
Number of times this error occurred
Total Overcharge
Total amount overcharged across all occurrences
Status
Detected, Action Needed, Claim Filed, Resolved, Dismissed
Detected Date
When the issue was identified
Actions
File Claim, Dismiss
Filing Claims
Click File Claim on any actionable item
Optionally provide:
Amazon Case ID (if you have already opened one)
Notes for your records
Submit the claim
Bulk actions: Select multiple items and click Bulk File Claims or Bulk Dismiss.
Pro tip: When filing weight/dimension claims, always request a cubiscan in your notes. A cubiscan is Amazon's official remeasurement process that permanently corrects the recorded dimensions for your ASIN. Without a cubiscan, the same error may reoccur.
Fee Audit Review Process Template
Use this structured process to maximize your fee audit results:
Weekly Review (15 minutes)
Monthly Deep Review (45 minutes)
Quarterly Strategic Review (1 hour)
🔍 Filters
Marketplace
All Marketplaces, or select specific
Audit Type
All, Referral Fee, FBA Fulfillment, Closing Fee, Wrong Category, Weight/Dimension
Status
All, Detected, Action Needed, Claim Filed, Resolved, Dismissed
Detail Side Panel
Click any row to open a detailed view:
Full fee breakdown with expected vs. actual calculations
Link to the product on Amazon
File Claim / Dismiss buttons
Historical context (when first detected, how many occurrences)
Best practice: Always open the detail side panel before filing a claim. The full fee breakdown helps you write more specific notes that improve your claim's approval chances.
Running an Audit
Click Sync at the bottom of the page to trigger a new audit scan. The Last Audit timestamp shows when the most recent scan completed.
Allow processing time. A full fee audit can take 5-30 minutes depending on your catalog size and the number of transactions being analyzed. Do not close the page during a sync.
🔄 Before & After: Impact of Fee Auditing
Fee errors detected per year
0-2 (manual spot checks)
20-100+ (automated scanning)
Time spent on fee review
0 hours (not done)
2-3 hours/month
Annual fee overcharges identified
EUR 0 (unknown)
EUR 1,000 - EUR 15,000+
Category errors caught
Rarely
Within days of occurrence
Weight/dimension corrections
Only if noticed by chance
Proactively detected and filed
Recovery rate
Near 0%
70-90% of filed claims
Seasonal & Timing Advice
January and June : Amazon's fee change windows. Amazon typically updates its fee schedules in January (effective February) and June (effective July). Run a complete audit within 2 weeks of any fee change. New fee tiers may be misapplied to your products, especially if Amazon's systems reclassify your product's size tier.
After listing updates: If you update your product's weight, dimensions, or category on a listing, run a fee audit 7-14 days later. Amazon's systems may not immediately reflect the changes, and you could be overcharged during the transition period.
Q4 volume check: During Q4, your order volume increases significantly. This means fee errors are multiplied across more transactions. An overcharge of EUR 0.50/unit that affects 5,000 units in Q4 alone is EUR 2,500. Run weekly audits during October through December.
New product launches: When you launch a new product, Amazon assigns initial weight, dimensions, and category during the first FBA receiving. Check the fee audit within 2-3 weeks of your first FBA shipment being received, this is when classification errors most commonly occur.
⚠️ Common Mistakes to Avoid
Mistake 1: Assuming Amazon's fees are always correct. Amazon processes billions of transactions. Their systems make mistakes. Do not assume that because you are a small seller, fee errors do not apply to you. Even sellers with 10-20 ASINs frequently find overcharges.
Mistake 2: Only checking fulfillment fees. Referral fee errors and category misassignments can be more expensive than fulfillment fee overcharges. A wrong category applying a 15% referral fee instead of 8% on a EUR 30 product costs you EUR 2.10 per unit, far more than most fulfillment fee discrepancies.
Mistake 3: Filing a claim without requesting a permanent fix. If Amazon reimburses you for a weight/dimension error but does not correct the recorded measurements, the same overcharge will continue on every future order. Always request a cubiscan or dimension update alongside your reimbursement claim.
Mistake 4: Dismissing small per-unit overcharges. An overcharge of EUR 0.30/unit seems trivial. But if you sell 200 units/day, that is EUR 60/day, EUR 1,800/month, and EUR 21,600/year. Always calculate the annualized impact before dismissing.
Mistake 5: Not running audits after Amazon's fee schedule changes. Amazon announces fee changes in advance, but the actual application can be inconsistent. Products that were correctly classified before a fee change may be incorrectly classified afterward if Amazon's systems reassign size tiers or categories.
## 🔧 Troubleshooting
Why does the audit show zero issues?
Your fees may actually be correct. Not all accounts have fee errors at all times.
Run a fresh sync. Click Sync and wait for the audit to complete. The "Last Audit" timestamp should update.
Check your marketplace filter. You might be viewing a marketplace where you have no sales.
Verify your account connection. Navigate to Settings > Connections and confirm your Amazon SP-API (Selling Partner API) access is active and has the required permissions.
The "Expected Fee" seems wrong: how is it calculated?
SellerMagnet calculates the expected fee based on:
Amazon's published fee schedule for the relevant marketplace and time period.
Your product's actual weight and dimensions (from your listing or last known cubiscan).
The correct product category based on your listing's browse node.
If the expected fee seems too low or high, check that your product listing has accurate weight, dimensions, and category information.
I filed a claim for a category error, but Amazon says the category is correct.
Amazon's category assignment is based on the product's browse node, which may differ from what you expect. To resolve this:
Check your product's browse node in Seller Central under "Edit Listing" > "More Details."
Compare the browse node's fee category against Amazon's referral fee schedule.
If the browse node is wrong, submit a "Change product category" request in Seller Central with evidence (competitor products in the correct category, Amazon's own category guidelines).
Amazon corrected the dimensions but the overcharge still shows.
After Amazon performs a cubiscan and updates the dimensions:
Future orders will be charged correctly.
Past overcharges are not automatically refunded. You need to file a claim for the historical overcharges.
SellerMagnet will continue to show the historical overcharge until you file a claim or dismiss it.
Why do some issues show as "Detected" instead of "Action Needed"?
"Detected" means SellerMagnet identified a potential overcharge but the confidence level is not yet high enough for a claim. This might happen when:
The fee discrepancy is very small (under a threshold).
The product's dimensions are ambiguous (close to a size tier boundary).
Additional data is needed to confirm the overcharge.
These issues may move to "Action Needed" as more transaction data accumulates, or you can manually review them and file if you have supporting evidence.
❓ FAQ
How far back can I claim fee overcharges?
Amazon's policy allows claims for fee errors going back up to 90 days for most fee types. Some categories may have different windows. File promptly, the sooner you claim, the more likely it is to be approved.
What is a cubiscan and how do I request one?
A cubiscan is Amazon's official process for remeasuring your product's weight and dimensions at the fulfillment center. You can request one by opening a case in Seller Central under "FBA Issues" > "Product dimensions are incorrect." Amazon will remeasure the product at the next available opportunity and update the recorded dimensions.
Does SellerMagnet check fees across all my marketplaces?
Yes. Fee Audit scans all connected Amazon marketplaces. Each marketplace has its own fee schedule, so an ASIN may be correctly classified on Amazon.de but incorrectly classified on Amazon.fr. Use the Marketplace filter to review each one separately.
Can Amazon change my product's category without notifying me?
Yes. Amazon periodically reassigns browse nodes and categories based on their catalog algorithms. These changes can affect your referral fee rate without any notification. This is one of the main reasons to run fee audits regularly.
What if my product is right on the boundary of a size tier?
Size tier boundaries are strict (e.g., "Small Standard" vs. "Large Standard"). If your product is close to a boundary, even a 1cm measurement difference can change the fee tier. In these cases, consider reducing packaging dimensions to firmly place the product in the smaller (cheaper) tier.
How does Fee Audit differ from the Reimbursements tool?
Reimbursements focuses on lost, damaged, or missing inventory : physical discrepancies in your stock. Fee Audit focuses on financial overcharges. Amazon charging you the wrong amount for fees. Both are forms of money recovery, but they address different types of errors.
Will fixing a fee error retroactively refund all past overcharges?
No. Correcting dimensions or category only fixes future charges. For past overcharges, you must file a separate claim for the historical transactions. SellerMagnet tracks the total historical overcharge amount to help you file accurately.
How often should I run a fee audit?
At minimum, monthly. Ideally, weekly during high-volume periods (Q4) or immediately after Amazon announces fee schedule changes. Set the Sync to run and review results during your regular business review cadence.
💡 Tips
Pro tip: Run a fee audit monthly, especially after Amazon's annual fee changes (usually in January and June). Category and dimension errors can persist for months if not caught.
Weight & dimension discrepancies are among the most common FBA overcharges. If you spot these, consider submitting a cubiscan request to Amazon to update your product's recorded dimensions.
Pro tip: Keep a record of your actual product weights and dimensions in a spreadsheet. When SellerMagnet detects a dimension discrepancy, you can quickly verify it against your records and include the correct measurements in your claim notes, this significantly increases approval rates.
Pro tip: After a successful cubiscan correction, check the same ASIN on all marketplaces. Amazon's dimension data is not always synced across regions, your product might be correctly measured on Amazon.de but still wrong on Amazon.fr or Amazon.it.
➡️ What's Next?
Reimbursements (Lost & Found)Inventory PlannerLast updated