Many online stores force you to sign in or create an account, enter all of your shipping information, and maybe even put in your credit card number before you can find out the shipping cost. How frustrating is that, especially when the shipping cost will help you decide whether to make a purchase at all? Try posting something on Ebay without a shipping quote–you won’t get bids–you’ll get requests for the shipping cost.
Some online stores, like PetFoodDirect.com, get it right: the first time you go to your cart, regardless of whether you’ve signed in or given any other information at all, you can enter your Zip Code and see the cost of shipping the current contents of your cart. After that, each time you change the contents of your cart, the shipping cost updates automatically.

Certainly we appreciate this as users–there are almost no barriers between us and the information we want, and we can quickly use the automatic shipping calculation to help us make purchasing decisions.
But this function probably also benefits the store, beyond the simple advantage of providing a function users like. See, when you collect address and credit card information, you put the user in checkout mode. Sure, that’s what you want–once a user starts checking out, they’re likely to finish, right? It’s the equivalent of being at the head of the checkout line in a brick and mortar store.
True, but in a physical store, the cashier doesn’t add a shipping cost that you couldn’t see while filling your cart. And, in an online store, it’s easy to abandon your cart if you see the final total and decide it’s too high. If shoppers can see shipping costs incremented as they shop, they can adjust their purchases with shipping costs in mind–there’s no surprise at the end of the checkout process.
Maybe someone who was going to buy two things will see the shipping cost and remove one of the items from their cart–but wouldn’t you prefer to have a customer buy one item, rather than abandon the whole cart after being surprised at the shipping cost? Even better, maybe a shopper will notice that adding another item to the cart has little or no effect on the shipping cost, and will decide to buy that extra item.
PetFoodDirect.com capitalizes on that second possibility by showing you items that you can add to your cart without increasing your shipping cost:

That trick always gets me to add several items to my order. I only go to Pet Food Direct to get one kind of cat food that I can’t get locally–I get the rest of my pet supplies in a physical store. But whenever this web site reminds me that cat treats and toys can hitch a free ride to my front porch, I throw a couple more items in my cart. If I didn’t have this information until I was just a click or two from finishing my order, I know I wouldn’t bother to go back into shopping mode to get them–they’re too easy to grab on my next run to the local pet store. But because this site gives me the info when it’s convenient to use it, they get more of my money!
You’re absolutely right about informing the user as they proceed through the purchase funnel. Yesterday, I was placing an order on a photo printing and framing website. I bailed out at the end once I saw that they were going to charge me nearly as much for shipping as the total cost of what I had ordered.
In retrospect, I didn’t abandon because it was an unreasonable fee; it was the shock of seeing my order total nearly double at the end of the process.
Well said, Tari. I’ve never seen a site that displays shipping costs like the two you cited here, but I’ll be on the lookout for them – that’s really smart.
Personally, I’m a big fan of sites with flat-rate shipping – for example, orders over $50 only cost $5 (or NOTHING) to ship. I’m more likely to spend a little more to get cheaper shipping, especially if it’s a clothing site having a sale.
And speaking of eBay, if you’re selling something for 1.99 and the shipping is 9.00? Yeah, I’m not bidding on that.
Lots of online electronic stores such as Frys, Newegg and Tiger Direct give a shipping calculator two clicks into the site when you are on your shopping cart. It’s great for people who don’t like surprises, like to browse and like to find the best deal. Shipping costs generally make or break my decision on whether or not to buy online or not. I was pleasantly surprised to find out recently that Sears loves to ship things for free! =)
I agree, free or flat rate shipping is really the way to win. But if you’re going to charge based on size and weight for shipping and handling, don’t be coy about it. You win by telling users what they want to know.