Overview

Amazon is retiring the weekly restock limits that have governed Fulfillment by Amazon (FBA) inventory for years and replacing them with a monthly capacity allocation system. The new model, announced for rollout this quarter, measures space in cubic meters, provides three‑month visibility, and adds a fee‑based reservation program for extra storage. Sellers who rely on predictable replenishment cycles should adjust their planning now to avoid disruptions.

Key Points

• Monthly limits replace weekly caps — Inventory allowances are set once per month for each storage type, removing the need to re‑calculate every seven days.
• Three‑month rolling forecast — Amazon publishes a confirmed limit for the next month and estimated limits for the following two months, giving sellers a longer planning horizon.
• Cubic‑meter measurement — Limits are calculated on volume rather than unit count, aligning space allocation with the actual footprint of each product.
• Capacity reservation program — Sellers can bid for additional cubic meters beyond their base allocation; the highest bids receive the extra space.
• Predictable release schedule — Monthly limits appear during the third full week of each calendar month on the FBA dashboard and are also sent by email.

How the New Monthly Capacity System Works

1. Limit calculation — Amazon evaluates each seller’s Inventory Performance Index (IPI), recent sell‑through rates, forecasted demand for individual ASINs, and overall warehouse capacity. For example, a seller with an IPI of 85 may receive a base allocation of 8 m³ for standard‑size inventory, while a seller with an IPI of 60 might be assigned only 4 m³.
2. Volume‑based reporting — The FBA dashboard now displays the total cubic meters used and the remaining capacity. A compact product line such as phone cases (0.001 m³ per unit) could translate to a limit of roughly 8,000 units within an 8 m³ allocation, whereas a single piece of furniture occupying 0.5 m³ would consume half the monthly quota.
3. Three‑month visibility — In the third week of the month, Amazon posts the confirmed limit for the upcoming month (e.g., 8 m³ for May) and provides estimates for the next two months (e.g., 7.5 m³ for June, 7 m³ for July). Sellers can use these figures to schedule shipments and negotiate with suppliers.