Safety stock is the minimum inventory level at which you should reorder a SKU to avoid going out of stock before new inventory arrives. Setting accurate safety stock levels in ShipHero ensures you receive an alert at the right time to reorder. This article walks through how to calculate the right safety stock quantity and how to set it in ShipHero.
Step 1: Calculate your total lead time
Add up the expected calendar days for each stage of your replenishment cycle. Production Lead Time is the number of days from when you submit a PO to your manufacturer until inventory is ready to ship. Transit Lead Time is the number of days to ship from your manufacturer to Manifest's warehouse. Manifest Receiving Lead Time defaults to 5 calendar days — this assumes a compliant ASN with a 3 business day receive plus a buffer for weekends.
Example: 10 days production + 5 days transit + 5 days receiving = 20 days total lead time.
Step 2: Find your average sales velocity in Shopify
Look up units sold per calendar day for the SKU. Manifest recommends using the last 90 days as your baseline. Adjust this figure up or down based on forward-looking forecasts such as upcoming promotions or seasonal demand.
Example: 15 units sold per day average over the last 90 days.
Step 3: Choose your desired days on hand for safety stock
This is the buffer of inventory you want to maintain above zero at all times. Manifest recommends a minimum of 15 days on hand as a safety stock target for each SKU.
Step 4: Calculate your safety stock alert quantity
Formula: (Total Lead Time + Days on Hand Desired) × Average Daily Sales Velocity = Safety Stock Alert Quantity.
Example: (20 days lead time + 15 days on hand desired) × 15 units per day = 525 units. Set your reorder alert to 525 units for this SKU and place a PO with your manufacturer as soon as the alert triggers.
How to set your reorder level in ShipHero:
Log into your ShipHero portal at shipsfor.us and click Products in the left-hand navigation. Find the SKU you want to set the level for and click into it. Find the Reorder Level field for the Manifest primary warehouse and enter your calculated safety stock quantity. Press Enter to save.
To set reorder levels in bulk across your full catalog, contact Manifest's account managers — they can upload reorder levels on the backend for some or all of your SKUs at once.
How to set up low stock email notifications:
Log into your ShipHero portal at shipsfor.us and go to Settings in the left-hand navigation. Find the Email Notifications section. Under Inventory, enable the notification for when your available quantity dips below your reorder level. Set the frequency to Daily. Enter your email address, press Enter, and click Save at the bottom of the page.
Important: Manifest must enable low stock notification emails from the backend in ShipHero before these alerts will send. Contact Manifest's account managers the first time you set up a reorder level or low stock notification so they can activate this for your account.
To understand how backordered units appear in ShipHero see How to View Out of Stock SKUs and Backordered Units. For inventory level definitions see Product Page Terms & Inventory Levels.