Shopping cart abandonment is every online merchant's worst fear.
After all, with all that you invest in marketing your website, it's painful to leave money on the table when would-be buyers don't convert to sales.
In this article, I'll share some ways to improve your shopping cart that I've used or seen used by other savvy online retailers.

1. Add Product Thumbnail Images: It's easy for visitors to forget what they added to their cart.
   Remind them by displaying a small product image next to the name.
   Remember, visitors don't know the product names as well as you do, so they need a visual reminder.
   
2. Your Just X Dollars away from Free shipping: Most e-commerce sites offer free shipping at a certain level.
   Remind your customers of this by displaying a prominent message letting them know how much more they need to spend to receive the promotion.
   
3. Buy X Get X Free: If you offer Buy one get one (BOGO) promotions, the shopping cart is a great place to display a message such as "Buy 1 more, get a 3rd FREE.
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4. Show Shipping Prices: For me, the thing that frustrates me most is when websites require me to enter my shipping info in order to calculate the shipping price.
   Simplify this by showing the shipping prices as early as possible.
   If you website calculate shipping prices based on the destination zip code, allow visitors to calculate the cost without having to enter all their personal info.
   
5. Show Shipping Times estimate: UPS, Fedex, and USPS offer different service time commitments to different parts of the country.
   Show a map of these estimated to shipping times to re-assure your customers they will get their order on tine.
   
6. Show What Method(s) order will ship: For many, the shipping method is as important as the shipping price.
   Some customers may have reservations about certain shipping methods.
   In addition, customer with rural address may only be able to get service from UPS or Fedex.
   Customer with PO Boxes will only be able to get deliveries from US Mail.
   
7. Cross-sell Items: The shopping cart is a great place to suggest similar items to that which are already in the cart.
   Just make sure the suggestions does not get in the way of the checkout process.
   
8. Up-sell Items: The shopping cart is a great place to let customers know about another product that may better serve their needs.
   Again, remember to soft sell so as to not confuse the checkout process.
   
9. Link to the Product Page: It's very easy to forget the features or other details about the products in your cart.
   Make it easy for your buyers to get back to the product page by providing a link from the shopping cart.
   
10. Feature Comparison: Show as much detail as possible on the cart page in order to let shoppers compare features.
    If you can't fit all the relevant information, include a "compare" link that allows them to compare all the features at a glance.
    
11. Progress Indicator Bar: People want to know that your checkout process is fast and easy.
    Display a progress indicator to let them know where they are, and how much further they need to go.
    
12. Make Your Cart Button Highly Visible: Above anything else, the "Checkout" button should be the most prominent feature on the shopping cart page.
    Make it large and bold enough to reach out and grab the user's attention.
    
13. Add the word "Checkout" to Cart Button: Most site's have a ubiquitous "View Cart" button on every page of the site, usually located in the upper right hand of the page.
    Consider also including the word "Checkout", since not everyone knows that "View Cart" is the first step to checking out.
    
14. Express Checkout: Make repeat purchases quick as easy by allowing return customers to login from the shopping cart page.
    
15. Email Customers with Abandoned Carts: An extremely effective way of capturing lost sales opportunities is to email those customers who abandon their shopping carts.
    Better yet, offer them a coupon or some other discount to come back and finish the purchase.
    
16. Show Stock on Hand: There's no greater way to stress urgency than to let customers know how much product you have on hand.
    While you might not want to show the exact quantity in inventory, you should definitely warn them when a product is close to selling out.
    
17. 1 Click Ordering: Surprisingly, a great way to increase your conversion is to skip as much of the shopping cart/checkout process as possible.
    Pioneered by Amazon, 1 click ordering is a great way to speed up the checkout process.
    
18. See More Items Like Those In Your Cart: Give them an incentive to spend more by suggesting other items similar to those already in the shopping cart.
    
19. Live Chat Link: Don't let customers abandon their order due to a nagging question.
    Provide an easy way to get an instant answer to their query.
    
20. Prominent Phone Support Number: Again, always provide an easy way to speak to a live person.
    
21. Show Payment Options Early: Customers will be curious as to what payment options you accept early on in the process.
    Let them know by displaying credit card logos, the Paypal logo, and an e-Check representation.
    For an example of this, checkout the shopping cart on C28'sJesus t-shirts store.
    
22. Auto-Submit Form Changes: It's common for customers to change the quantity of an item in the cart, and then click "checkout" instead of first clicking the "update" button.
    You can prevent later confusion by refreshing the quantities in their cart automatically if it is changed.
    
23. Save for Later Button: Let's face it, not everyone will complete the purchase the same day they add the item to their cart.
    Assure them that the items will remain in the cart by allowing them to save it for later.
    Better yet, email them after a certain amount of time to remind them.
    
24. Security and Privacy Reminder: Assure your visitors your website is secure and trustworthy.
    Display emblems such as the Hacker Safe logo or the BBB Online logo.
    Also, let your visitors know their personal information will be kept private by linking to your privacy policy.
    
25. Link to Your Return / Exchange Policy: One of the greatest hesitations to buying is worrying about returning a product to an online retailer.
    Assuage the fears of your customers by linking to your "No Hassle Return Policy.
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I sincerely hope some of the ideas above will be helpful to your online business.
Remember, each shopping cart feature that helps to improve or simplify the shopping process will become a competitive advantage and another memorable reason for your customers to come back.
For more conversion tips, please visit my website marketing blog.