Feterun

As announced in December 2023, the FBA low-inventory-level fee will go into effect on April 1, 2024. This fee applies to products with consistently low levels of inventory relative to their unit sales, which is also referred to as your historical days of supply. Maintaining sufficient inventory levels allows Amazon to effectively distribute products across our fulfillment network, which improves shipping speeds for customers and helps drive more sales for you.
How it will work
Starting April 1, the transition period will begin. You will still be charged the fee on eligible products shipped with historical days of supply below 28 days. Then, we will credit back any charged low-inventory-level fees for units shipped between April 1 and April 30. You can expect to see this credit in May.
Starting May 1, the fee will be charged without a credit back. You can avoid the fee by ensuring that either the long-term historical days of supply (last 90 days) or short-term historical days of supply (last 30 days) are above 28 days (4 weeks). April will give you an opportunity to understand if your current inventory management actions will effectively avoid the fee, or if there are adjustments you can make to avoid this fee so you're prepared going forward.

Monthly inventory storage fee changes
Amazon charges monthly inventory storage fees for the space your inventory occupies in fulfillment centers. Starting April 1, 2024, off-peak monthly inventory storage fees (January-September) will be reduced by $0.09 per cubic foot for standard-size products. This change will first be reflected in May 2024 charges for storage that occurs in April 2024. There will be no change to off-peak monthly inventory storage fees for large bulky or extra-large (previously called oversized) products and peak monthly inventory storage fees for standard-size, large bulky, and extra-large products.
Storage utilization surcharge changes
Starting April 1, 2024, Amazon will introduce more granular fee tiers to the storage utilization surcharge and will start applying the fee to Professional sellers with a storage utilization ratio above 22 weeks. Amazon will exclude inventory aged between 0 and 30 days from the surcharge. This change will first be reflected in May 2024 charges for storage that occurs in April 2024.
Starting June 1, 2024, products that are auto-replenished by Amazon Warehousing and Distribution are eligible for a storage utilization surcharge waiver. This change will first be reflected in July 2024 charges for storage that occurs in June 2024.