eCommerce Stock Management & Checkout Session Timing

Stock management in an eCommerce Checkout presents a genuine conflict of interest between the customer and the retailer.

Having placed an item in their basket, the customer will be justifiably indignant if that item is removed from their basket during the checkout process – imagine standing in line at the supermarket waiting to pay, only to find out that when you reach the cash register your basket is empty!

Conversely, the retailer needs to have stock available for sale, and so will not want items held in the baskets of customers who do not intend committing to a final purchase.

eCommerce Stock Availability

The first issue to recognise here is that checkout is about payment, not shopping. As we have said all along, keep the checkout clear, simple and short, putting nothing in the way of the customer once they have committed to buy.

Stock availability should always be made clear prior to checkout, and stock reserved at an appropriate point, until or unless the customer is deemed to have abandoned it.

So the two decisions we need to make are at what point is stock reserved for sale, and what rules should apply for releasing that stock to other customers?

1. When should stock be reserved for sale?

The simplest option is to reserve stock when it is added to basket. If there is high basket abandonment rate or if stock is in short supply and high demand there may be a case for considering alternative options.

  • One is to reserve stock when the customer clicks to begin checkout and the other is only to reserve stock only once purchase is complete. The challenge with these options is managing communication with the customer when stock runs out – one suggestion is to check stock in the customer‟s basket every time a new page is loaded and flag up prominent out-of-stock apologies, when necessary.

2. What rules should apply for releasing that stock to other customers?

  • Never releasing stock once it has been reserved (added to a basket) is inefficient and probably exceeds customer expectations. If I come back to a site two months after my first visit, I don‟t expect the retailer to have refused to sell it to anyone else in the meantime.
  • Releasing stock from baskets once a shopping session ends is both prudent and reasonable. To cater for sessions that don‟t end (computer in sleep mode and browser left open) a cut-off needs to be set – this could be anything from 10 minutes to an hour of browser inactivity and frequently this will be based on session-timing.


The challenge, again, is communicating your stock management rules to the customer.

How do we establish best practice from these various options?

  1. Doing nothing about stock reservation is not an option.
  2. A reserve-on-add-to-basket should be adopted as the most simple and effective stock reservation rule. Reserve-on-entry-to-checkout and reserve-on-purchase are both technically feasible but counter-intuitive to the customer and messy to communicate convincingly. They also achieve nothing that cannot be equally well achieved by a stock release policy.
  3. Stock management is most effectively tightened by session management (session duration). However, it must be communicated clearly to the customer and preferably the count-down to session timeout should also be shown.

Find out more about Emarkable’s eCommerce Solutions and how to avoid the loss of of eCommerce Checkout Information.

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We are always happy to answer any questions. Contact the team by phone on (01) 808 1301, or email us at

Richard Coen

With over 21 years of experience in Digital Marketing, 31 years in sales and 25 years in business development, Richard assists companies to develop key growth strategies on a local or international basis. He can assist marketers to achieve balance in their approach to key areas affected by the growth in digital marketing.