customer tries to BIN the shipping calculator tells them that the zip code is inavlid

[pjcdn2005]

Is this is a U.S. buyer and is your shipping option Expedited USA?

If both answers are yes, the problem likely is that the dimensions entered are too small for expedited USA. The minimum dimensions are 21cm x 14cm x .5cm.  When the seller enters those numbers, the calculator does not warn them that they will not work.

To confuse matters, the minimum measurements for expedited within Canada are 10cm x 7cm x 1mm so shipping will work for Canada if the package is that small but won't work for the U.S.

The online Canada Post calculator will also give you a cost if you enter the smaller dimensions in their calculator even though their site states what the minimum measurements are. Obviously there is a glitch with the Canada Post calculator

You have 20+ items that do not show shipping for the U.S.

For items under 1kg you can also use small packet USA or tracked packet USA. (or light packet for items less than 2cm thick)

Small and light packet tracking do not have tracking or insurance  but for smaller inexpensive items they usually work well.

Customers are attracted by lower shipping costs and because we are competing against the lower U.S. shipping costs, it's best to use the service with the lowest cost when possible.

Small and tracket packet minimum for the U.S. and international - 14cm x 9cm x 1mm

Light packet has the same min and max as lettermail.

[pjcdn2005]

You should go look at your listings go to the shipping tab and change it to different locations to see what you are charging for shipping.

You are charging $72 shipping to the UK for a $24 coloring book. I doubt that anyone would be willing to pay that.

There is a small risk when using small and light packet because of the lack of tracking but there are very few parcels that actually do get lost. After I ship an item I always send a message to the buyer to confirm that their item has been shipped and to give them an approximate time of arrival so that they are not expecting it to take the same amount of time as if you were in the same country as them. I often mention that the item was sent with Canada Post as another reminder that I am in another country.

Many sellers use self insurance for less expensive items. That is basically charging a little bit extra for shipping each item and then putting that money in a virtual cookie jar to use when a package is lost or when you have a claim.

For most sellers, it works better to use air mail rather than surface as that can take 4 - 12 weeks and most people won't wait that long.

Shipping is one of the most complicated parts about selling here. You really should do some research so that you know that you are using the right service for your products.