Streamworks Blog
Did you know that your letter-size mailpiece won't qualify for automated rates unless it meets the aspect ratio This is just one aspect of a mail piece to keep in mind.
What is the anatomy of a mail piece?
A mail piece (or mailpiece) is any letter-size or flat-format mailer designed for USPS automation. Its anatomy includes the return address, address block, postage permit, endorsement copy, and the overall layout that keeps it within USPS aspect ratio and automation guidelines.
Let's go over it together!
Return Address
The Return Address, which goes in the upper left corner of your mail piece, has several requirements:
- Use with Endorsement Lines (either printed or embedded in IMb™)
- Mail with precanceled stamps
- Mail with a company permit imprint
- Priority Mail®
- Periodicals in envelopes or wrappers
- Nonprofit mail (return address must match permit address exactly)
- Official Mail
- Certified Mail™ if return receipt requested
- Package Services
- Parcel Select®
- Registered Mail™
- Insured Mail
- COD Mail
Address Block Preferences
An Address Block is a group of different fields that make up your recipient's address. The most common components include:
- name
- street address
- city
- state/province
- zip code,
- country (if needed)
Depending on the type of mailing you're doing, you may add a prefix (Mr., Mrs., Ms.) or substitute the First and Last Name for something more generic, like "Current Homeowner."
There are requirements for an address block as well.
Mailpiece Requirements
- An Address block area of 2" x 4"
Window Envelopes Requirements
- Window size of 1.5" x 4.25" (taller if more than six address lines)
- At least .625" from the bottom edge
- At least .5" from the left edge
- At least .125" clearance from left edge or copy
Permit Specifications
Using a postage permit must meet specific requirements to ensure your mailpiece is mailed correctly.
Mailpiece Requirements
- No smaller than .5” x .5”
- Minimum 8 pt type
- Color contrasts with background
Location options
- Upper right corner of the mailpiece
- Upper right corner of the address area
- To the right of address on the label
- To the right of the address through the window envelope
Endorsement Options
You can also include endorsement information on your mailpiece, such as callout information, special offers, urgent language, and more.
There are four places that you can place endorsement copy
- Under the Return Address
- Above the Address Block
- To the left of the Postal Permit
- Underneath the Postal Permit
Remember how we talked about the importance of aspect ratio at the top?
If you're wondering how to determine your aspect ratio, divide the length of your mailer by the height. If it's between 1.3" and 2.5", you are on your way to automation rates!
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