Seasonal stock is goods purchased in anticipation of increased demand in a certain period. For an e-shop it's one of the riskiest decisions of the year: buy too little and you sell out at the peak and lose orders, buy too much and you tie up capital in goods that lose value after the season. Plan from data – from sales for the same period in previous years, adjusted for growth and changes in the range – and split the purchase into several waves if the supplier allows it. Track stock turnover by category, not overall, because the average hides items that sit unsold for a year. Have a plan in place in advance for unsold goods: a gradual price reduction, bundles with current-range items, or a sell-off through another channel. Inactivity and waiting for the next season is the most expensive option.
See also: Seasonality of demand, Margin and discount promotions, Availability and Delivery Time.