Why can't I track a USPS First Class Large / Flat Envelope shipment?

Large Envelopes / Flats are serviced by USPS First-Class Mail. The USPS does not provide tracking on this service. You can contact the USPS for more information.

Difference between First-Class Mail and First-Class Package

First-Class Mail:

This service includes a package type called "Large Envelope/Flat".

This is essentially a flat envelope you would use to ship documents. It is the least expensive service you can get with USPS through ShippingEasy and it is not eligible for tracking services. Learn more about Large Envelope Flats

First-Class Package:

This service includes a package type we refer to as a "Thick Envelope (3/4")".

Often used for padded envelopes, it can be used to ship documents or thin objects that are less than 3/4" thick. It can be a little more expensive, but it does include tracking.

Even though USPS does not include tracking on the very cost-efficient First Class "Large/Flat Envelope", they do return an unusable reference number when a label is purchased. We agree it is confusing to all of us, including your buyers. So, we have hidden it across the board: SHIPMENT HISTORY and Shipping Confirmation Emails will not include this fairly unhelpful number.


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What is happening to First Class Mail.  It is taking days, and sometimes weeks, for the mail to be delivered to the designated party.  This is extremely frustrating!!!  I sent a letter from Central New York to Florida and it took 2 weeks and 2 days to arrive.  Extremely poor service!!!!!

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Hello Nancy,

I'm sorry to hear that your First Class packages and mail are taking longer than expected. I definitely understand how frustrating that can be especially with your customers having to wait even longer for their packages. Since it is First Class, it is considered the least expensive service you can get with USPS through ShippingEasy. That means that there is a chance it can take longer than usual. If you are wanting it to be shipped quicker, I would recommend shipping it via Priority Mail so that way, it'll cost a little more but it'll give you the peace of mind with both tracking, included insurance and a shorter time to get there.

Please let me know if you have more questions!

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I sent a large flat padded envelope on Dec 16,2019, and how do I know my party receiived it. I haven't heard from them? Thanks , Robert Murphy

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Hi Robert,

I have not been able to locate your ShippingEasy account to look up the shipment and tracking number.  If you are on a paid plan for ShippingEasy, please use the links at the top of the app to contact us via chat, email, or phone.  I will mention that for USPS shipments, the Carrier (USPS), would be the best resource for tracking down the shipment.  The Carrier would handle everything on their end once the shipment enters the mailstream.  Here is the Contact Page for USPS for your reference:  https://www.usps.com/help/contact-us.htm

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I sent a first class mail to a domestic location from a 22312 zip code to 22079 zip code. It is domestic and it has been three days. I want to know how i will be able to know if the person received it.

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Good afternoon Biruktawit,

I am afraid I was unable to find your ShippingEasy account. 

USPS First Class tracking does not have a guaranteed delivery date. If you purchased a First Class parcel that includes tracking you can use that tracking number to investigate the shipment on the USPS website


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