Amazon's New 90% Delivery Requirement: Why Fulfillment Problems Often Start Before Shipping

Amazon's 90% Requirement Is More Than a Delivery Metric

Beginning September 30, 2026, Amazon will require seller-fulfilled shipments to Amazon Business customers in the U.S. to maintain a Business Hour Delivery Rate of at least 90%, measured over a rolling 14-day period.

At first glance, this appears to be a shipping or carrier-performance requirement.

But for eCommerce operators, delivery performance can be influenced long before a package reaches the carrier.

Inventory availability, warehouse execution, handling-time assumptions, replenishment timing, and demand planning can all affect whether an order ultimately reaches the customer within the promised window.

That makes the 90% requirement more than another marketplace KPI. It is an opportunity to examine the operating chain behind the metric.

A Late Delivery Can Start Before the Carrier Has the Package

When a delivery-performance metric falls below target, the carrier is an obvious place to look. Sometimes that is exactly where the problem sits.

But not always.

Consider an order that ships late because the warehouse could not dispatch it on time. The immediate issue appears to be fulfillment speed. Look one step further back, however, and the SKU may not have been available at the correct fulfillment location when the order was released.

Or inventory may have been available, but the warehouse or 3PL was operating beyond the capacity assumed in the seller's handling time.

In another case, replenishment may have arrived later than planned because the purchasing decision was made too late. That decision, in turn, may have been based on a demand forecast that no longer reflected actual sales velocity.

The final symptom is the same: delivery performance deteriorates.

The root causes are very different.

That distinction matters because improving the wrong part of the operation will not necessarily improve the KPI.

Trace the KPI backward

At McKeeleen Advisory, we prefer to work backward from the performance signal rather than assume the visible problem is the root cause.

For Business Hour Delivery Rate, that means tracing the operating chain:

Business Hour Delivery Rate

↓

Carrier transit performance

↓

Warehouse dispatch

↓

Pick and pack

↓

Order release

↓

Inventory availability

↓

Replenishment

↓

Demand planning

Each step asks a different management question.

If carrier transit is the problem, changing inventory policy will not solve it.

If orders are leaving the warehouse late, the issue may be capacity, cutoff times, handling-time settings, or 3PL execution.

If the SKU is unavailable when the order arrives, management needs to understand whether the problem came from inventory positioning, replenishment timing, an inbound delay, or demand exceeding the plan.

And if replenishment consistently happens too late, the analysis needs to move further upstream into forecasting, supplier lead times, purchasing rules, and inventory targets.

The objective is not to react to the KPI. It is to identify which operational decision is driving it.

What Sellers Should Review Before September 30

Sellers affected by the new requirement should not wait for Business Hour Delivery Rate to fall below 90% before investigating their operation.

A useful review should cover the full fulfillment chain.

• Inventory availability: Are the right SKUs actually available at the fulfillment location when orders are placed?

• Warehouse or 3PL execution: Are pick, pack, and dispatch times consistently meeting the assumptions built into handling times?

• Order cutoff times: Do marketplace settings reflect the warehouse's real operating schedule and carrier pickup windows?

• Carrier performance: Which services, lanes, or destinations are responsible for late deliveries?

• Replenishment: Are stock shortages or late inbound inventory causing orders to wait before fulfillment?

• Demand changes: Are recent sales patterns materially different from the demand assumptions used to position inventory?

• Exception visibility: Can the team identify which SKUs, orders, fulfillment locations, or processes are creating the greatest delivery risk?

Amazon also recommends that sellers use reliable carriers, maintain accurate handling and transit times, and consider tools such as Automated Handling Time, Shipping Settings Automation, and Amazon Buy Shipping where appropriate.

Those tools can help improve execution, but they should sit inside a broader operational review.

If the underlying problem is inventory availability or replenishment timing, changing a shipping setting alone will not fix it.

From Marketplace KPI to Management Action

Amazon's 90% Business Hour Delivery Rate requirement is specific to Amazon, but the management problem behind it is much broader.

Businesses increasingly have operational data coming from marketplaces, warehouses, 3PLs, suppliers, inventory systems, and sales channels.

The challenge is rarely a lack of numbers.

The challenge is connecting those numbers well enough to understand what requires action.

At McKeeleen Advisory, we look at inventory, demand, replenishment, and operational performance as connected parts of the same decision system.

A fulfillment KPI deteriorating may begin with inventory availability.

An inventory problem may begin with replenishment timing.

A replenishment problem may begin with supplier lead time or purchasing decisions.

And a purchasing decision may ultimately trace back to the demand plan.

This is why operational reporting should do more than tell management whether a KPI is red or green.

It should help answer three questions:

What is happening?

Why is it happening?

What should we do next?

For Amazon sellers preparing for the September 30 requirement, the 90% target is important.

But understanding the operating chain behind that 90% is what gives management the ability to improve it.

Better visibility should lead to better decisions, not just better dashboards.

Source and Further Reading

This Insight is based on Amazon's announcement of the new Business Hour Delivery Rate requirement for seller-fulfilled shipments to Amazon Business customers in the United States, effective September 30, 2026.

Amazon Seller Central: New business hour delivery requirement for seller-fulfilled shipments

McKeeleen Advisory

Inventory • Demand • Replenishment • Operational Performance

Practical operational support for eCommerce businesses that need clearer visibility into inventory, demand, replenishment, and the decisions behind performance.