SAFETY STOCK English meaning

But if the lead time is already long, that product might be out of stock for months. The same goes in case of a supply chain issue, like a material shortage. For example, microchip shortages in 2021 significantly increased the time customers had to wait for a new car, made some features unavailable, and drove prices up. Let’s say one of your popular products goes out of stock and customers keep asking for it. If the lead time with your supplier is short, meaning you can get new inventory in mere days, this is a small issue.

Even when the demand average suddenly spikes or your delivery doesn’t arrive on the average expected time, you will still have enough stocks for your customers. It’s easy to use up stocks, but it’s tough to gain a customers’ trust again once you lose it, so you should avoid letting safety stock decline. There are certain times of the year when retailers can expect an influx of sales, the holiday season being the most prominent.

Hence be diligent and make sure that you are holding only that much quantity that can be utilized in the peak period easily. In this case, the estimated lead time is 20, the actual lead time is 25, and the lead time variance is 5. A supplier estimated that it would take 20 days for stocks to arrive.

Greasley’s method adds the average demand factor to the earlier mentioned Heizer and Render’s formula. Online shoppers might see your product out of stock and look for an instant alternative on a competitor’s website. Customers that used to visit your brick-and-mortar store regularly may stop coming in after they’ve walked out empty-handed a few times. When your customers rely on you for specific products, and run into an empty shelf (either virtual or physical), you risk losing them.


This means you can ship customers’ orders on time and maximize sales while ensuring your supply chain process is streamlined economically. The ideal solution should be able to account for every relevant factor across all sales channels. Providing optimal safety stock recommendations at the location and SKU level. The main goal of a good safety stock level is to absorb the variability of demand. This formula helps retailers monitor net inventory while the resulting value should be higher than the reorder point to avoid running out of stock. These calculations can be done manually on spreadsheets using a safety stock equation, however as a retailer grows this approach is hard to scale.

  • Inventory management is the science of dealing with uncertainty, and the variables it considers can never be completely controlled.
  • Now that you’ve learned about the importance of having a safety stock.
  • For example, you can decide to keep two weeks’ worth of safety stock for an item.
  • If demand for your product fluctuates but your lead time is relatively predictable, this can be a helpful method.

Assume that a company uses the economic order quantity (EOQ) model to determine the amount of product or materials it orders. Since the model requires an assumption (estimate) of annual demand, there is a risk that demand will be greater than the estimate used. As a precaution, the company may decide to always have an additional 100 units on hand as its safety stock. If demand is not constant, the company could increase the quantity of its safety stock during its peak sales periods and then reduce the quantity during periods of low sales. Safety stock is an additional quantity of an item held by a company in inventory in order to reduce the risk that the item will be out of stock. Safety stock acts as a buffer in case the sales of an item are greater than planned and/or the company’s supplier is unable to deliver additional units at the expected time.

Without safety stock, this change in demand becomes a missed opportunity. Reorder point is a predefined inventory level at which you replenish your stock. There’s an important distinction between safety stock and a reorder point. That will depend on numerous factors such as the size of your business, the quality of your data, your inventory mix, and so on. Retailers often don’t realize that the amount they are losing in lost sales is higher than their overstock fees.

Your discount has been successfully applied and will be reflected after adding items to your cart. By keeping stock for each segment of the manufacturing process in reserve, one part won’t slow down or stop the others. In essence, you are decoupling each part of your manufacturing process, so they aren’t dependent on each other to operate. Choose the formula that best serves your store’s circumstances and includes all relevant variables. If there are significant variations in your supplier’s schedule, Heizer and Render’s formula is the way to go.

For example, if you know that every Cyber Monday you double your online sales, you can effectively calculate how much safety stock you should have on hand for upcoming holiday inventory prep. That way, you won’t risk losing out on sales on one of the hottest buying days of the year. Other costs are intangible, and result in an opportunity cost to your business. Customers who are ready to buy but find their desired product is out of stock may not purchase anything, which is a lost sale. That customer may also go to a competitor, which can result in lost sales in the future.

d. Increased inventory costs:

Use Shopify POS to forecast demand and calculate safety stock to protect against costly stockouts. Safety stock, also known as buffer stock, is like an emergency fund. If you sell more of a given product than you expected, your supply chain is disrupted, or your merchandise gets damaged, safety stock allows you to keep selling that product regardless. There are several safety stock equations retailers use to determine what is a good safety stock level for their inventory mix.

Basic Safety Formula

As a sourcing company with ten years of credibility, we are experts in assisting clients to maintain safety stock inventories. We’ll share our knowledge about what a safety stock is, why you need it, and how you can do a safety stock calculation for your own business. All of that money that was spent on excess jackets could have gone to pay for operating expenses.

Forecast demand

In addition to weather events and labor shortages, currently, there are supply chain disruptions caused by the backup of suppliers post-pandemic. Shipments are taking longer to be distributed to warehouses for delivery to customers. Additionally, since everyone is clamoring for the same space, it causes bottlenecks, which is frustrating to both customers and retailers. Getting ahead of these kinds of problems by determining the safety stock level for items should be part of any inventory strategy.

The general formula

Small-business owners can gauge the optimal amount of safety stock over time, depending on current consumer demand, lead times, and other factors. Stockouts have a host of negative implications for small-business owners, leading to a loss of sales, decreased customer satisfaction, increased operational costs, and more. Having safety stock can help business owners avoid running out of stock even when unexpected events occur. Safety stock is a buffer that protects businesses from unexpected demands.

Safety stock with EOQ (economic order quantity)

If that’s the case for you, here are three different safety stock formulas that can better align with your business goals. The goal is to hold just enough safety stock to avoid either of these two extremes. You can achieve this with accurate data and the right safety stock formula. Without safety stock, your customers may end up disappointed because the item they want isn’t available. With too much safety stock, however, you’ll have a risk of spoilage, dead stock, and high storage costs.

This is a choice often made to save money on upfront costs; purchasing, transportation, and storage. They may also be trying to avoid over-stocks which leads to drastic markdowns that cut deep into the revenue. When planning inventory, retailers should be purchasing an additional quantity of products to protect themselves from lost revenue and to maintain a consistent shopping experience for the consumer. Safety stock makes it easier to operate a small business smoothly and efficiently. Customers can purchase the products they love, suppliers aren’t rushed, and employees aren’t overworked.

It is determined by several factors like lead time variability, forecast accuracy, and service level. Each place has a demand pattern of its own, and you have to adjust it accordingly. So now you’re probably asking yourself, how much safety stock should I keep on hand? closing entries types example If you stock too much, you’ll end up paying more in storage costs, run the risk of theft or damage to your products as well as the potential of products expiring. On the other side of the coin, if you stock too little, you’ll be setting yourself up for failure.