I use the calculator on USPS to get my shipping costs to send invoices for things I sell on Facebook What is happening is with the parcel or ground shipping. For instance the USPS ground rate is $20 for shipping calculated. When I go to print my label I use the drop down menu for parcel and use my same weight and dimensions. The price to ship isn't 20 its 40! I take the package to the post office and they check and it is indeed 20 to ship. So I write out a label and ship from there. Inconvenient and no discount on shipping cause I can't ship using PayPal cause the calculator is wrong. PayPal has told me its USPS charging the wrong price. Doubtful. Help!
I'm sorry to hear that there is a difference in what the USPS site shows for a package and what shows in the shipping that you purchased through PayPal. I would recommend using the shipping calculator on the PayPal site for accuracy. The link to that is in this article.
I hope this helps!
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