Amazon Restock Planning: Days of Cover, Lead Times and Peaks

Key takeaways: Restock planning is a weekly check of three numbers per ASIN: days of cover, true lead time and the demand curve ahead. Reorder when cover drops to lead time plus a safety margin, size the order to 60 to 90 days of cover, and add the peak uplift eight to ten weeks before the event. Ad spend and restock decisions have to be made together.

The three numbers

Days of cover is available units at Amazon plus units inbound, divided by the average daily units sold over the last 30 days. It tells you when you will hit zero if nothing changes. Use the child ASIN, not the parent, because the popular size runs out first.

True lead time is the full chain from placing a purchase order to units showing as available in FBA: production, quality check, freight, customs, delivery to the fulfillment center and Amazon's check-in. Sellers often count production and freight and forget that check-in during Q4 can take two to three weeks on its own. Add up every stage from your last three shipments and use the longest, not the average.

The demand curve ahead is what changes the daily sales rate. A Prime Day deal, a Q4 uplift, a planned price cut or a new campaign all raise the rate; an off-season lull lowers it. A restock plan built on the trailing 30 days will always be short going into a peak and long coming out of one.

When to reorder and how much

The reorder point is true lead time plus a safety margin. Three weeks of safety is a reasonable starting point for a stable product; volatile products or long ocean-freight chains need more. When cover reaches that point, order enough to bring the ASIN back to 60 to 90 days of cover at the forecast rate, not the trailing rate. That band is wide enough to absorb a good month and narrow enough to stay clear of long-term storage fees and Amazon's capacity limits.

Planning for peaks

Peak planning starts eight to ten weeks before the event. For Prime Day in July, that means stock decisions in April and May. For Black Friday and December, it means orders placed by late August and shipments leaving in time for Amazon's published inbound cut-off dates, which are usually set for early to mid November for the holiday period; check the current dates in Seller Central each year.

Estimate the uplift from your own history. Pull last year's daily units for the four weeks around the event and compare them with the four weeks before. If you did not run the event last year, use the category's typical behavior and plan conservatively, because a stock-out during Prime Day loses more than a few unsold cartons cost. Then decide what happens to ad spend: a deal that sells through the peak stock in 36 hours and leaves you at zero for the rest of the week has cost you rank as well as sales.

Strategy & growthAmazon Seasonal Planning: The Calendar We Work FromThe Amazon year has four planning windows, each starting six to ten weeks before the event. The calendar we run every account against, and what happens in each.

Ad spend and restock are one decision

The most common cause of a stock-out we see is not a slow supplier. It is a successful campaign. Ad spend scales, velocity doubles, and the restock plan built on last month's rate is suddenly three weeks short. Every scaling decision needs a stock check first: at the new expected rate, does the ASIN still have eight or more weeks of cover, and has the next order already been placed? If not, the scaling waits, or the restock is brought forward. The same logic runs in reverse when stock is heavy: ad spend and price become the tools that bring cover back into the band.

The weekly routine

Once a week, for every child ASIN that matters:

1. Update available, inbound and reserved units from the FBA inventory report.
2. Recalculate days of cover at the trailing rate and at the forecast rate for the next eight weeks.
3. Flag any ASIN below reorder point or above 120 days.
4. Cross-check the flags against planned ad changes, deals and price moves.
5. Record the decision, even when it is "no action", so the log shows why an order was or was not placed.

That routine takes under an hour for most catalogs and removes nearly all of the emergency air freight.

One more input belongs in the check: Amazon's capacity limits. The amount you are allowed to hold in FBA depends on your Inventory Performance Index and Amazon's own forecasts, and it is shown in the capacity monitor in Seller Central. A restock plan that calls for more units than the limit allows has to be split across shipments or supported by a capacity request, and that takes time to arrange.

D14Too much stockinventory back to 60–90 days of cover before long-term storage fees bite.

E5Stock and cash checks before we scaleno stockouts and no negative cash months caused by a scaling decision.