Live USPS Shipping Rates

USPS is a popular shipper and fairly easy to setup live shipping rates with your WP EasyCart ecommerce plugin.  Here we outlines the steps to make it easier for you to create a USPS live account, access the right credentials, and then establish a connection within EasyCart.

How Live Shipping Rates Work

It is important to know how your ecommerce store handles live shipping rates so you have a clear understanding of what they CAN do and what they CAN NOT do.  Live rates will provide you with rates from the carrier based on specific data your site sends.  For example, when you create a product in EasyCart, you should assign it default package Length, Width, and Height dimensions as well as a Weight value.

WP EasyCart will use these to create a ‘best fit’ package and combined weight from the shopping cart of all shippable items and when a customer is checking out, it will send their ship-to postal code and your ship-from postal code to get rates.

What Live Shipping Rates Don’t Do

It is also important to know that live shipping rates stop there… they provide customer shipping rates directly from the carrier.  They do not submit a package or purchase shipping labels as part of a post-order fulfillment process.  The WP EasyCart Premium edition does offer several options to connect with providers who specialize in this, such as ShipStation or, where you can purchase actual labels and align what rate the user purchased vs actual label choices.

Live shipping rates is also limited in that it doesn’t receive discounted rates if you use a third party system such as shipstation,, goshippo, pirateship, etc.

Setting Up USPS Live Shipping

WP EasyCart makes it easy to setup live rates, but you do need to acquire the proper account with the carrier to make the connection.  All of the programming is done for you, but you must get an account from the proper locations.  These can often be hard to locate, so we will walk you through it here.

Step 1:  Getting your USPS Account


You will need to sign up for the USPS Web Tools API portal.  Simply click Register Now.

Step 2:  Complete Registration Form

Here you need to fill out the USPS registration form and submit for approval.

Step 3:  API Username from USPS

They will email you a API Username that you must keep.  This Username gives you access to all the price calculator and address services they provide.

Example format of username:  12WPEASL38293  or 55ABCDEF12345

Now that we have an account and username with USPS, we can open WP EasyCart -> Settings -> Shipping Settings to make the connection.

Notice in this example below we have entered the API Username along with the postal code we will ship from, that is all we need to enter and it should show you a green ‘Connected‘ status when you enter this.  If it shows a red ‘Error’ then you know you should check your username or contact USPS.  Connected means it has successfully contacted and retrieved a rate from USPS and we are ready for the next step.

Conversion Rate:  This is useful as a global rate adjuster.  You 1.00 means the rate returned is what will be shown.  If you wish to add 10% to every rate returned from a carrier, you can do so here by inputting 1.10 to make it 110%.


Step 4:  Setting up Individual Rates

Now that we are connected to a live carrier, we can setup which live rates we wish to show to our customers.  Just go to the WP EasyCart -> Settings -> Shipping Rates panel and we can engage ‘Live Shipping Rates‘ as our choice for store shipping.

Notice in this example, we have turned on ‘Live Shipping Rates’ at the top and it has pre-installed some Live Rates for us down below.  Here you may add to or remove rates based on your preference and situation.

You can also setup an override price, free shipping threshold as well as a zone to each shipping rate.

  • Override Price:   This will simply make the rate show a set price you establish here.
  • Free Shipping Threshold:  If you wish to have shipping be free on one special live rate when a value in the cart is reached, you may do so here.  For example…  $100 dollar orders or more qualify for free USPS ground shipping.  You can target that specific rate and value to achieve this promotion.
  • Shipping Zones:  This needs to be used carefully.  Zones are simply a post-address filter and are not a way to limit shipping.  The API is smart, it will limit and only show the rate if it ships to that location.  We recommend you set this to ‘No Zone’ unless you explicitly know what you are doing.

Special Considerations:

It is important to understand how live rates work.  Just because you setup a shipping rate does not mean all customers will see them.  For example ground shipping to an island doesn’t work, or some locations never provide 2nd or next day air.  Some rates are specifically for international users, while shipping within the same city can also require special rates.

For this reason, we recommend you start out by adding as many of the rates and possible and testing it out on various important addresses and locations you plan to ship to.  Make sure ‘SOME’ of the rates return in each situation.  You may have 10 shipping rates setup in WP EasyCart, but a customer with a certain address may only see 2 or 3 of the rates due to their location and address!



Step 5:  Product Considerations

Now that you are connected, a couple checks are needed on your products to make sure they are shippable, have dimensions and weights, and will respond to live shipping calculations.  Go to the WP EasyCart -> Products panel and edit one of your shippable items.

In this example, we have edited a product and added weight and dimensions.  Note that the dimensions are excluded.  You may set ‘Standard’ or ‘Metric’ as your units within the WP EasyCart -> Settings -> Shipping Settings panel.  Standard units (lb/in) or Metric (oz/cm) are sent to carriers depending on your selection.

Notice that under the Shipping Options we also must ‘Enable Shipping‘ so this item will get into our calculation.   A neat feature in WP EasyCart is you can also add a handling fee that gets added to all the shipping rates.  Maybe you want an extra $5.00 for handling per item or just one time…  just enter your value here for this product.  You may add a global handling fee in our shipping settings panel as well as many other options!


Step 6:  Complete!

That’s it, you have successfully connected to and setup live shipping rates and your shopping cart will now pull shipping rates based on the total contents of shippable items within the customers cart.  Every order will show you the customers selected shipping choice AND what they paid for the shipping service.  You can now use any shipper service and pay for shipping accordingly.

Don’t forget, you can use WP EasyCart Premium to connect to various third party programs for actual post-order fulfillment and label purchasing!  Check out the PRO version which has live shipping rates + the Premium edition which offers live shipping AND connections to third party shipper services!


Video Resource:

We also have a video resource to see an overview of setting up live shipping as well within WP EasyCart

Video Guide – Live Shipping with USPS, FedEx, UPS and more!

EasyCart Professional and Premium come with all our live carrier rates from USPS, FedEx, UPS, DHL, Australia Post, and Canada Post for accurate rates based on weights and dimensions.
View All Videos Here




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