Even now, you can still see some articles referring to an Ecommerce system as a Shopping Cart Software. While this is far too simplistic to think about digital commerce as a simple shopping cart implementation, it highlights the shopping cart’s key place in any Ecommerce project.

A cart is the heart of a project where all Ecommerce complexities come together, and its implementation needs to be fast, reliable, and transparent.

Add to Cart

When a shopper adds a product to the cart, the shop should give clear feedback on this action. To achieve this, in addition to implementing a regular cart page, it is a good practice to create a mini cart to give a visual indication of how many products are in the cart. When a customer clicks on the mini-cart icon, it should show a quick overview of the shopping cart content without interrupting the shopping experience.

For example, when a customer adds a product to the cart, ASOS shows a small animation – the mini cart appears to show the cart’s content, then folds in after a few seconds

Cart Page

Users make their final purchase decisions when they are on the cart page. Shoppers add products to a cart to review or compare the items they have chosen, check whether the order total meets their budget or whether they qualify for free shipping. So, design your cart page in such a way that it assists your shoppers in their buying decision.

The key principles for displaying cart contents are clarity and control. It should be easy to understand what is in the cart and the final cost, including shipping and taxes. It should be easy to make changes, like updating the quantity or removing products.

For these operations to be fast, the Ecommerce project team should continuously focus on optimizing the shopping cart calculation.

Zalando checkout example

Cart page should also show applicable taxes – included in the price for selling in Europe or as separate line items in North America. See Gross vs. Net prices in the Price Section.

Guest Cart

Customers could start adding products to a cart before they create an account or sign-in. It would be a very frustrating experience for them to lose their cart’s content after login or registration. Your site should be able to convert an anonymous cart to the cart of an authenticated user.

When a guest buyer hasn’t registered for a storefront account before, it would be good to save Cart ID in the cookie. When the buyer returns to the storefront later, she inherits the cart ID and can continue shopping with the same cart. The cart should also be preserved for a user who starts with the anonymous cart and registers later. In other words, never lose the cart content.

Cart with Subscription Products

If your business sells subscription products, the implementation of the cart page becomes more complicated. The most complex use case comes from selling a combination of regular and subscription products.
Let’s say you are on a telco site and are buying a cell phone, headset, and internet plus a mobile plan. For some products, customers are going to pay now, while others are charged regularly. The cart page needs to show recurring and one-off prices separately. It is also crucial to display two totals – how much the buyer will pay now and how much she would be charged monthly.

shopping cart with subscription product implementation

Multiple and Shared carts

In some scenarios, a single cart is not enough. Businesses with physical stores and online commerce may offer a customer an option to add a product to the buy-online cart or pick-up-in-store cart. We can see here the example from German DIY store Hornbach and IKEA


While IKEA calls one of the cart Notepad or Wishlist, it is a cart from the implementation perspective, as it calculates the total, and customers can pick up the order in the store.

There are a couple more use cases that require multiple carts.

On some marketplaces, customers can opt for multi-vendor checkout. In such a case, a shopping cart is split, and the customer goes through checkout multiple times.

Split, multivendor checkout

B2B Cart

And, of course, multiple carts are used in B2B commerce, where several complex purchases could be in progress simultaneously.

👩‍🎓🛒👨‍🎓 Shopping cart in B2B. What is different?

Shared shopping carts in B2B ecommerce

 While most B2C buyers are purchasing for themselves, in B2B, shopping and checkout may not necessarily be done by the same person. Quite often, one employee, a subject matter expert, would identify the products. The second employee (a manager) would approve the purchase. And an employee from the procurement department would place the order. In B2B, the ordering process needs to be optimized for the collaboration of multiple users. B2B shoppers can assign names to these carts and configure them under specific organization accounts or contracts.

In B2B, we need multiple carts and the ability to share these carts with other people.

For example, Spryker’s B2B solution allows customers to create any number of shopping carts. Carts can be shared between different users, and a user can have the right to modify the cart or only to view it.

Recently, online grocery stores have also started to offer cart sharing functionality for families.

Cart collaboration is not only needed between different buyers but also between a merchant and a buyer.

Modern Ecommerce systems add a human touch to an online shop by allowing sales or customer support people to assist customers during the purchasing process using the same storefront interface.

They have profound knowledge of the company’s product range and the shop system and can perform various activities on behalf of customers. This includes selecting the right products for customers to buy, highlighting promotions and cross-sell opportunities, reviewing their carts, and even going through the checkout process.

Below you can see an example of Spryker’s Agent Assist feature. Agent logs into the store and selects a customer he wants to assist. After that, the Agent can view the customer’s shopping carts and help in completing the order.


Cart Validation and Calculation

There is a lot of complexity in the Shopping Cart implementation. Every operation on the cart – like removing or adding a product, increasing quantity, or applying coupon results in cart recalculation. Before a customer can place an order, a cart must be validated to ensure product availability, confirm that the correct prices are used, and promotions are applied according to their rules and priorities. See the Promotions section for more details on Cart Promotions. Many companies need to implement additional cart validation logic like constrains on min or max order value or limitations on product quantity a single customer can buy.

Applied discounts and taxes need to be allocated per each cart item to allow the correct refund calculation later.

The cart logic should be aware of product combinations and relations between products. For example, when quantity is increased for a bundle, it is increased for all products that make up the bundle. If a customer removes a product with an option (like gift wrapping), both the main product and its option need to be removed from the cart.

Recovering Abandoned Carts

We use the term Cart abandonment in digital commerce to describe instances of incomplete purchases. It refers to eCommerce store visitors who add products to their carts and drop out before completing the checkout process. Here are statistics of cart abandonment for different industries. As you can see, the numbers are staggering.

Reasons for shopping cart abandonments

It is essential to track and monitor cart abandonment rates and invest in getting some of these customers back.

Here are techniques and tools merchants can use to recover this lost revenue.

  • Sending Cart Abandonment Recovery Emails
  • Using Remarketing Ads
  • Encouraging customer to finish the purchase with AI Chat Bots
  • Displaying Exit Pop-ups

Cart Abandonment Recovery Emails

Cart abandonment email automation is the most broadly used technique to tackle these percentages. Using marketing automation tools, you can set up email templates and schedule one or several to go off within a designated amount of time. The shop visitors, receiving a personalized email reflecting their cart content plus an additional incentive (like a discount coupon), are very likely to complete their purchase.

Abandoned shopping cart statistics per industry

Source: Moosend

Email serves as a reminder, and businesses use it to offer additional motives, such as a discount coupon or free shipping. That way, companies manage to recover almost one-third of abandoned carts.

Retargeting Ads

Another powerful technique for recovering abandoned carts is remarketing with targeted ads. Studies show that in comparison to standard display ads, remarketing ads are 76% more likely to be clicked! This is because they are highly relevant to customers. Here are examples of targeted ads from Facebook, Google, and Twitter.

Chat Bots

AI-powered chatbots is a newly emerging approach to reducing cart abandonment and recovering some of the lost revenue. Here is how it could be done using Octan AI Messenger Chatbot.

Abandoned shopping cart recovery

Wish List

Wish lists are a middle ground between purchasing and forgetting. Wishlist enables customers to bookmark their favorite products and continue when they return. They can share wish lists with friends via social media or email. It is a great way to engage with customers as merchants can send Email reminders when a wishlist product has a low stock or price drop.

A wish list is an especially convenient feature for mobile shoppers who research products online while on the go. Customers may want to bookmark the product and complete the purchase when they have more time on their hands.

Wish lists are used across all industries.

Wish lists can encourage users to sign up for an account they would not have otherwise and allow businesses to engage these prospects later in marketing campaigns.

You can give even more benefits to your customers by supporting multiple wish lists. Selecting a hotel takes time. You need to evaluate different options and coordinate with your travel companions. On, I can create a wishlist for every location I plan to visit, send them to friends, and compare.

Amazon, true to its nature as a store for everything, gives shoppers the ability to create a range of shopping lists for different purposes.

Wish lists or Shopping lists are even more critical in B2B Commerce as repetitive purchases are more common – for example, you can have a list of products to buy for each new hire or weekly office supplies.

As we discussed above, B2B sales is a collaborative process, so it should be possible to share shopping lists with co-workers. B2B shopping lists can be quite large, and it helps to have multiple options for adding shopping list items to the cart.

Here is the example of Shopping Lists implementation in Spryker.

Next Section

online checkout


The checkout flow is critical for the business. Avoid common mistakes. Discover the pros & cons of one-page , multistep, mobile checkouts, registered vs. guest, and how to provide a distraction-free experience.