Inventory how-to

How often should you reorder inventory

Reorder as often as your sales velocity and supplier lead time require, not on a fixed calendar schedule.

Short answer: Reorder as often as your sales velocity and supplier lead time require, not on a fixed calendar schedule. Most small stores check reorder points weekly, but fast-moving SKUs may need checks every few days and slow movers only once a month.

Why "once a month" rarely works

A single reorder frequency across all products wastes time or causes stockouts. A SKU that sells 10 units a day needs far more frequent attention than one that sells 10 units a year. Set the review frequency per product based on how fast it sells and how long the supplier takes to deliver.

Tie frequency to the reorder point, not the calendar

The real trigger for ordering is hitting a reorder point: daily sales times (lead time plus safety days). If you check stock weekly but your reorder point is set correctly, you will always catch the SKU in time, even if you only count stock once a week. The calendar check is just a system for noticing when the trigger has been hit.

Fast movers vs slow movers

For your top sellers, check stock two or three times a week, because a few days of extra sales can eat through a smaller buffer fast. For slow movers, once a month is usually enough since their reorder point sits much further out in days of stock. Group your catalog into a few speed tiers and assign a check frequency to each tier instead of treating every SKU the same.

Step by step

  1. List every SKU with its average daily sales over the last 28 days.
  2. Calculate each SKU's reorder point: daily sales x (lead time + safety days).
  3. Sort SKUs into tiers: fast, medium, slow movers.
  4. Set a check frequency per tier, for example fast movers twice a week, slow movers monthly.
  5. Compare current stock on hand to the reorder point at each check.
  6. Place an order whenever stock on hand is at or below the reorder point, not on a fixed date.
  7. Review the tiers every few months as sales patterns change.

Worked example

A store sells a phone case at 6 units a day. The supplier lead time is 10 days and the store keeps 4 safety days. Reorder point = 6 x (10 + 4) = 84 units. If stock on hand drops to 84 units or below, it is time to reorder, whether that happens on day 3 of the week or day 20. A slow-moving accessory selling 1 unit every 3 days with the same supplier has a reorder point of about 0.33 x 14 = 4.7, so it only needs checking once a month.

How SteadyShelf helps

SteadyShelf calculates the reorder point and order-by date per SKU automatically using your 28-day sales window and each supplier's lead time and safety days, then sends a weekly reorder email so you do not have to manually check stock levels against reorder points. It does not set different check frequencies per tier for you. you still decide which SKUs warrant extra attention between the weekly emails.

$29/month flat, unlimited products and suppliers, 30-day free trial. Run the numbers now with the free reorder point calculator.

SteadyShelf is launching on the Shopify App Store. Join early access to get the install link first.

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FAQ

Do I need to reorder every SKU on the same day?

No. Each SKU has its own reorder point based on its own sales speed and its own supplier lead time. Group orders by supplier when it makes sense to save on shipping, but the trigger date will differ by product.

What happens if I check stock too infrequently?

You risk missing the reorder point for fast-moving SKUs and running out of stock before the replacement order arrives. Build in enough safety days to cover the gap between your checks, or check fast movers more often.

Let SteadyShelf do this math for every SKU

Order-by dates per supplier, seasonal forecasts and draft POs for your Shopify store. $29/month after a 30-day free trial.

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