What Are Non-Machinable Stamps? (2022 USPS Guide)

What are non-machinable stamps? Mail sorting machines help USPS to be fast. These machines can sort up to 36,000 pieces of mail per hour! However, when the mail is not standard-sized, the machines have trouble. That's why there is a surcharge for non-machinable stamps. If you have any questions about non-machinable stamps, now you know where to find the answers.

what are butterly stamps and non-machinable stamps

What are non-machinable stamps?

The United States Postal Service offers a variety of stamps for different purposes, and one type of stamp that is available is called a non-machinable stamp. These stamps are designed for use on First-Class domestic mailpieces that do not meet the designated sizing standards.

Some examples of items that would require a non-machinable stamp include square greeting cards, rigid letters, or lumpy letters containing pens or keys.

These items are not able to be sorted by machines and must be hand-canceled, which results in a surcharge. When choosing stamps for your mail, be sure to take into consideration whether or not the item will require a non-machinable stamp to avoid any additional charges.

What is non-machinable mail?

In the simplest terms, non-machinable mail is any piece of mail that USPS machines can’t sort due to an irregular size or shape. letters that don’t meet these criteria slow down and sometimes even jam machines.

To avoid any mechanical issues, USPS employees remove unusually-sized mail and hand-cancel the stamps. Not surprisingly, hand sorting takes longer than machine sorting. As a result, USPS tacks on a surcharge for mail that doesn’t adhere to its guidelines for machinable mail.

The good news is that there are only a few types of mail that USPS deems non-machinable: square envelopes, envelopes with clasps or pockets, rigid items, or items with odd shapes. With a little bit of knowledge about sizing and weight requirements, you can easily avoid the then-Machinable surcharge.

A letter that is the standard size according to USPS is:

  • Rectangular
  • At least 3½ inches high x 5 inches long x 0.007 inches thick.
  • No more than 6⅛ inches high x 11½ inches long x ¼ inch thick.

Is it possible to stamp non-machinable stamps indefinitely?

When you see the words “non-machinable Surcharge” on a stamp, it means that the stamp will always be valid for the current non-machinable surcharge. In other words, if you buy non-machinable stamps today and USPS increases the price tomorrow, you’ll still be able to use the stamps you purchased even though you paid less than the current value.

This is similar to how Forever Stamps work, in that they will always be valid for first-class postage, regardless of price changes. So if you’re looking for a way to save on postage, non-machinable stamps are a good option. Just be sure to check the current surcharge before you buy, so you know how much postage you’ll need.

Is it possible to use a non-machinable stamp on regular mail?

non-machinable stamps are those stamps that are not able to go through the automated machines at the post office. This can be for a variety of reasons, such as the stamp being too large or having an irregular shape.

While technically you can use these stamps for regular mail, it is not advised. This is because non-machinable stamps come with a surcharge in addition to the standard first-class postage rate.

Therefore, unless your letter is non-standard sized, you will be overpaying if you use one of these stamps.

Is it possible to use two non-machinable stamps for the rest of my life?

Whether or not you can use multiple Forever Stamps instead of a non-machinable stamp depends on the value of the stamp. Currently, a Forever Stamp is valued at $0.58. A non-machinable stamp, on the other hand, is valued at $0.88. So, if you're trying to use Forever Stamps to cover the cost of a non-machinable stamp, you would need two stamps (which would cover $1.16 worth of postage). However, since the non-machinable stamp only costs $0.88, using two Forever Stamps would be overpaying for postage.

Thus, it's more financially prudent to use a non-machinable stamp if you can get your hands on one. However, in a pinch, using two Forever Stamps will get your letter or package where it needs to go - even if it does cost a bit more than necessary.

Where can I get non-machinable Stamps?

Although non-machinable stamps are available for purchase at your local Post Office, you may find it more convenient to buy them online or over the phone. You can buy non-machinable stamps on the USPS website or by calling 1-800-STAMP-24 (1‑800‑782‑6724).

If you’re buying stamps in person, you can purchase them individually. However, if you are buying non-machinable stamps online or over the phone, you’ll need to buy a sheet of 20. Although non-machinable stamps cost slightly more than regular stamps, they allow you to mail items that would otherwise require additional postage. As a result, they can save you time and money in the long run.

How much are non-machinable Stamps?

The current cost of a non-machinable stamp is $0.88. This includes the $0.58 First-Class postage fee, as well as the $0.30 non-machinable surcharge.

In comparison, a sheet of 20 non-machinable stamps retails for $17.60. This means that, if you're sending a letter or package that falls into the non-machinable category, you'll need to factor in this additional cost.

non-machinable items are usually those that are bulky, odd-shaped, or otherwise difficult to process by machine.

What are some of the distinctive characteristics of non-machinable stamps?

The United States Postal Service (USPS) defines a non-machinable letter as one with certain physical characteristics that make it difficult or impossible to process on automated equipment. Because these letters require additional handling, they typically cost more to mail than standard letters.

non-machinable letters typically have one or more of the following characteristics: rigid or bulky; odd-shaped; unable to lie flat; or less than 3-1/2 inches high and 5 inches long. In 2010, the USPS began featuring butterflies on all of its non-machinable stamps to make it easier for consumers to identify letters that require additional postage.

Greeting card companies also began printing a butterfly icon on cards that require a non-machinable stamp.

What is the non-machinable Surcharge for First-Class Mail?

The United States Postal Service charges a non-machinable surcharge to First-Class Mail when any of the following circumstances apply:

  • A letter with an aspect ratio (length divided by height) of less than 1⅓ or more than 2½ (square envelopes)
  • A letter that’s more than 4¼ inches high or 6 inches long and is less than 0.009 inches thick
  • A letter with clasps, strings, buttons, or similar closure devices
  • A letter that’s too rigid
  • A letter with a delivery address parallel to the shorter side of the mail item
  • A letter that contains items such as pens, pencils, or keys that create an uneven thickness
  • A letter that is poly-bagged, poly-wrapped, enclosed in any plastic material, or has an exterior surface made of a material that’s not paper


In conclusion, a non-machinable stamp is necessary for letters or packages that have any of the characteristics mentioned above. The current cost of a non-machinable stamp is $0.88. If you're buying stamps in person, you can purchase them individually. However, if you are buying non-machinable stamps online or over the phone, you'll need to buy a sheet of 20.

Although non-machinable stamps cost slightly more than regular stamps, they allow you to mail items that would otherwise require additional postage. As a result, they can save you time and money in the long run.

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author: patrick algrim
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Patrick Algrim is a Certified Professional Resume Writer (CPRW), NCDA Certified Career Counselor (CCC), and general career expert. Patrick has completed the NACE Coaching Certification Program (CCP). And has been published as a career expert on Forbes, Glassdoor, American Express, Reader's Digest, LiveCareer, Zety, Yahoo, Recruiter.com, SparkHire, SHRM.org, Process.st, FairyGodBoss, HRCI.org, St. Edwards University, NC State University, IBTimes.com, Thrive Global, TMCnet.com, Work It Daily, Workology, Career Guide, MyPerfectResume, College Career Life, The HR Digest, WorkWise, Career Cast, Elite Staffing, Women in HR, All About Careers, Upstart HR, The Street, Monster, The Ladders, Introvert Whisperer, and many more. Find him on LinkedIn.

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