Available to Promise (ATP)

Available to Promise (commonly abbreviated as ATP) is a concept within inventory management that refers to the number of products a business can confidently promise to deliver to customers — either immediately or within a specified time frame. ATP isn’t just about what’s physically sitting on the shelves right now. It’s a dynamic calculation that takes into account already reserved items, incoming deliveries, planned production, and customer delivery expectations. In other words, ATP is a key component of an efficient Warehouse Management System (WMS), where visibility and timing are everything.

Rackbeat September 26, 2025

What Does Available to Promise Mean in Practice?

Let’s say you have 80 units of a product in stock, but 50 of them are already reserved for ongoing orders. At the same time, 30 new units are expected to arrive from your supplier within three days. Your current ATP level — meaning what’s available to promise — is 30 units (80 – 50), and it will increase to 60 units in three days (30 + 30).

This calculation is essential when it comes to responding to customers quickly and accurately:
“You can receive 30 units immediately, and the remaining 30 on Wednesday.”
It improves not only customer service but also your procurement planning and reduces the risk of lost sales due to lack of visibility.

Why Is ATP Important?

Whether you operate in e-commerce, B2B wholesale or retail, accurate ATP calculations are a critical foundation for decision-making across sales, purchasing, and inventory.

When you have a clear overview of what’s actually available to promise, you can:

Fulfill customer needs immediately or provide realistic delivery dates
Minimize backorders and reduce unnecessary customer follow-ups
Optimize your inventory levels and free up warehouse space
Adjust reorder points and improve purchasing management
Enhance collaboration between sales, warehouse, and purchasing teams

With a well-functioning ATP setup, you strengthen the entire value chain — from the first customer inquiry to the final shipment. It’s a natural part of modern inventory management and a prerequisite for effective order management.

How Does Rackbeat Help You Manage ATP?

In Rackbeat, Available to Promise is not something you have to calculate manually. The system acts as an intuitive WMS, where your data is seamlessly connected across product cards, order workflows, and stock levels. You gain real-time insight into how many units are in stock, what’s already reserved, and what’s inbound — making it easy to know exactly what you can promise your customers.

Whether you’re working with sales orders, purchase orders, or stock transfers, ATP is automatically updated. This allows you and your team to make informed decisions — whether it’s about closing a sale, placing a new purchase order, or planning warehouse capacity more effectively.

Real-World Example

Let’s say you sell electronic components to manufacturing companies. You currently have 200 units in stock, but 150 of them are already sold and awaiting shipment. At the same time, 100 units are in transit from your supplier. A customer calls and wants to purchase 120 units as soon as possible.

With Rackbeat, you can, in just a few clicks, see that you have 50 units available to promise right now, and the remaining 70 can be delivered in two days. This allows you to say “yes” to the order right away and give the customer an exact delivery schedule — increasing both the chance of a sale and customer satisfaction.

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