Inventory how-to

How to plan inventory for subscription boxes

Subscription box inventory planning means forecasting demand for every component that goes into the box, not just the box itself, and ordering so all components arrive together before your pack date.

Short answer: Subscription box inventory planning means forecasting demand for every component that goes into the box, not just the box itself, and ordering so all components arrive together before your pack date. The key is treating the box as a group of SKUs with one shared deadline, then working backward from your pack date using each supplier's lead time.

Forecast by component, not by box

A subscription box is really a bundle of individual items. You need enough of each item to cover the number of boxes you plan to ship that cycle. If one component runs short, it can hold up the whole batch, so check stock on every component separately, not just the finished box count.

Work backward from your pack date

Subscription boxes run on a fixed schedule, so your planning is driven by a deadline rather than daily sell-through. Take your pack date, subtract each supplier's lead time and a safety buffer, and that gives you the order-by date for that component. Different suppliers will have different order-by dates even though everything needs to land by the same pack day.

Plan for subscriber count changes

Your box quantity depends on active subscriber count at the time of packing, which can shift due to new sign-ups, cancellations, and skips. Use your current subscriber count plus a reasonable growth buffer when calculating order quantities, and review it close to the pack date so you are not over or under ordering components.

Watch case packs and minimums against batch size

Components often come in case packs or have supplier minimums that do not divide evenly into your subscriber count. Round up to the nearest full case or minimum order, and keep the leftover stock as a starting buffer for the next cycle rather than letting it sit unused.

Step by step

  1. List every component in the box as a separate SKU with its own supplier and lead time.
  2. Set your pack date for the next cycle and work backward using each supplier's lead time plus safety days.
  3. Check current subscriber count and add a buffer for expected growth or skips.
  4. Calculate order quantity per component: subscribers needed minus stock on hand minus stock on order.
  5. Round each order up to the supplier's case pack or minimum.
  6. Place orders so the component with the longest lead time is ordered first.
  7. Confirm all components have arrived before the pack date, and note any shortfalls so you can substitute or delay.

Worked example

A store packs 500 boxes on the 1st of each month. One component, a candle, has a 20-day lead time from its supplier and the store adds 5 safety days, so the order-by date is 25 days before pack day. The store has 80 candles on hand and 0 on order, needs 500 for the cycle, so it needs to order 420 more. The supplier sells in cases of 50, so the store orders 440 (9 cases) and keeps the extra 20 as a head start on next cycle's stock.

How SteadyShelf helps

SteadyShelf can track each component as its own SKU, calculate order-by dates from supplier lead times, and round orders to case packs, which covers the per-component ordering side. It does not know your subscriber count or pack schedule, so you still need to set the order quantity target yourself based on how many boxes you are packing that cycle.

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

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FAQ

Can SteadyShelf forecast how many boxes I will need next cycle?

No. SteadyShelf forecasts sales velocity per variant based on recent order history, but subscription box volume depends on your subscriber count and churn, not product sales velocity. You need to supply the expected box count yourself, then use SteadyShelf for ordering the components against that number.

What if a component is also sold separately in my store?

Then that SKU has two sources of demand: regular sales and box demand. SteadyShelf will forecast the regular sales side from order history, but you need to manually add the box requirement on top before placing the order, since it has no way to know your subscriber count.

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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