Inventory how-to

How to plan inventory for summer products

Plan summer inventory by treating it as a separate demand curve, not an extension of your normal sales pace.

Short answer: Plan summer inventory by treating it as a separate demand curve, not an extension of your normal sales pace. Build up stock ahead of the season based on last year's summer sales plus current trend, then plan a clean exit so you are not stuck with leftover stock in October.

Separate the ramp-up from the steady state

Summer products usually have three phases: a build-up, a peak, and a wind-down. Your normal reorder math assumes fairly steady daily sales, so it will underorder right before the season starts and overorder right as it ends. Treat the ramp-up as its own planning problem: decide how much stock you want on hand by the date demand starts climbing, not just what covers current daily sales.

Work backward from your season start date. If you know sunscreen or sandals start selling in early May, count back your supplier's lead time plus your safety days and place that order in time to have stock landed and ready, not just ordered.

Use last year's numbers if you have them

If you sold the product last summer, look at the actual daily sales during peak weeks, not the yearly average. A product that averages 2 units a day across the year might sell 8 units a day in July. Use the peak figure to size your pre-season order, and the off-season figure to size what you keep on hand afterward.

If you have close to 13 months of sales history in the system, seasonal patterns like this get picked up automatically in the forecast. With less history, you need to make the seasonal adjustment yourself and treat the forecast as a starting point, not the final answer.

Plan the exit before you plan the entry

Decide early how you will handle leftover stock. Options include cutting the final order short so you sell through close to zero, planning a markdown in late August, or carrying a small amount into next year if it is not perishable or style-dependent. Whatever you choose, build it into your last order of the season rather than deciding in a panic when boxes are still arriving in September.

For new summer products with no sales history, order conservatively for the first cycle. Watch sell-through in the first one to two weeks and place a top-up order quickly if it is moving faster than expected, since lead time is now your biggest constraint.

Step by step

  1. Pull last year's daily sales for the summer SKUs during peak weeks, not the annual average.
  2. Set a season start date and count back each supplier's lead time plus safety days to find your must-order-by date.
  3. Place a pre-season order sized to peak daily sales, not current daily sales, using case pack and minimum quantities from the supplier.
  4. Mid-season, switch back to normal reorder monitoring using actual sell-through rather than last year's numbers.
  5. Pick an exit plan in advance: sell through to zero, markdown date, or carryover amount.
  6. Place your last order of the season early enough that it can still arrive and sell before demand drops.
  7. For brand-new summer SKUs, start conservative and reorder fast based on early sell-through.

Worked example

Last July, a beach-towel SKU sold 10 units a day at peak versus 1 a day the rest of the year. The supplier's lead time is 14 days and the store wants 7 safety days. Reorder point for peak season = 10 x (14 + 7) = 210 units. If the store currently has 60 on hand and 0 on order, the order quantity for 30 days of cover = 10 x (14 + 30) - 60 = 380 units, rounded up to the nearest case pack of 24, which is 384 units.

How SteadyShelf helps

SteadyShelf does not do per-season or per-location forecasting, so it will not automatically know "summer starts in May" for your store. With about 13 months of history it will start to reflect the seasonal pattern in its forecast, but for the first year or for the pre-season ramp-up you should override the suggested quantity manually based on last year's peak sales.

$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

What if this is the first summer I am selling this product and I have no history

Order a conservative first batch based on comparable products or your best guess, then watch sell-through closely in the first one to two weeks. Reorder quickly once you see real demand, keeping in mind your supplier's lead time, since you have no forecast to lean on yet.

How do I avoid being stuck with unsold summer stock in the fall

Decide your exit plan before the season peaks, not after. Cut your final order short so remaining stock sells through naturally, or set a markdown date in advance, and treat any leftover as a known cost rather than a surprise.

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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