How Many Stamps For Bubble Mailer? (All You Need To Know)

Mailing small or flat items that require a little cushioning is easy as can be – all you need is a bubble mailer, which you can find in most stores that sell office supplies. The only catch is figuring out postage.

Most bubble mailers are bigger than your average business envelope or greeting card. So, how many stamps do you need for a bubble mailer? Can you get away with one Forever stamp? If this is a question you have, you’re in luck – I have the answer below!

How Many Stamps For Bubble Mailer In 2024?

The number of stamps needed to mail a bubble mailer through the United States Postal Service depends on the dimensions and weight of the envelope in 2024. Mailers that are small and light enough may be eligible for First-Class Letter postage or one Forever stamp. Those that do not meet the requirements will need additional postage.

To learn more about the size and weight requirements for different mail classes when shipping a bubble mailer, a quick how-to guide, and how much you can expect it to cost, keep reading!

Is A Bubble Mailer Considered A Flat?

Let’s examine the dimensions USPS puts forth for Flats and what it considers to fall under the Letter category.

From there, you can figure out if your bubble mailer is considered a Letter, Flat, or something else.

That said, the dimensions for a Flat are:

  • Minimum: 6 1/8” high; 11.5” long; ¼” thick
  • Maximum: 12” high; 15” long; ¾” thick

Moreover, the dimensions for a Letter are:

  • Minimum: 3/5” high; 5” long; .007” thick
  • Maximum: 6 1/8” high; 11.5” long; ¼” thick

Additionally, First-Class letters eligible for mailing with just one Forever stamp (worth $0.58) must weigh no more than one ounce.

So, if you have your bubble mailer – and they come in many different sizes – at hand, get a ruler or tape measure and see which dimensions fit.

Also, if your bubble mailer falls under the Flats category, you know that you will need more postage than just a single Forever stamp.

Further, you can send a bubble mailer as a Flat, using stamps up to 13 ounces of weight (or seven Forever stamps); at, say, four ounces, that would cost $1.76 in postage.

What if your bubble mailer hits the height and length requirements but not the width – say, it’s thicker than three-fourths of an inch?

Then, you have a parcel on your hands. Fortunately, you can still send it First-Class, but you’ll use First-Class Package instead of First-Class Letter, and you won’t use stamps.

Ultimately, if you have any questions about your bubble mailer, you can always bring it to your post office and ask the clerk at the counter.

How Do You Ship A Bubble Mailer?

How Do You Ship A Bubble Mailer USPS

To ship your bubble mailer, you must first enclose everything you’re mailing and seal it up.

After that, you can use the guidance in the above section to figure out if you can send it First-Class Letter or if you need a package class.

Therefore, if it qualifies as a First-Class Letter or a Flat, and you have stamps on hand, you can just calculate the postage needed and apply it.

Then, leave it in your mailbox or drop it off in a USPS box or at your post office, and you’re done.

Remember, if the bubble mailer is too big or too heavy to qualify as a Letter or a Flat, you’ve got a parcel.

Provided it’s less than 13 ounces, you can ship it First-Class (any heavier, and you’ll have to choose from some of the other, slightly more expensive package options).

If you don’t have a scale at home, you can bring your bubble mailer to the post office, and an employee will help you at the counter.

However, if you have a scale and a business account, you can weigh the package at home and print a label with Click-N-Ship.

But, if you don’t have a business account, you will need to bring the package to the post office for postage.

Can You Just Put Stamps On A Bubble Mailer?

Yes, you can just put stamps on a bubble mailer if it meets a Letter or Flat requirements.

In comparison, shipping a package always requires a label, which you can print at home if you have a scale and a printer or bring into the post office.

Also, one of the nice things about a bubble mailer that qualifies as a package is that tracking is always included so that you can watch its progress to the destination.

How Much Does It Cost To Mail A Padded Envelope?

The cost of mailing a padded envelope depends on the size and weight.

For example, if your bubble mailer is small enough to qualify as a Letter, you only need one Forever stamp, which is $0.58.

However, Flats require additional postage after one ounce of weight.

Also, after four ounces of weight or dimensions larger than a Flat, Package postage for a shipping label is needed.

Fortunately, you can calculate your mailing costs using this calculator.

To know more, you can also read our posts on USPS 70 cent stamps, how many stamps for a manila envelope, and how many stamps per pound.


Bubble mailers may be so small and light as to require just one Forever stamp, but larger or heavier ones that qualify as Flats will require additional postage.

Further, bubble mailers are large enough to qualify as packages, but the boon is that those shipping classes, including First-Class, come with tracking.

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Marques Thomas

Marques Thomas graduated with a MBA in 2011. Since then, Marques has worked in the retail and consumer service industry as a manager, advisor, and marketer. Marques is also the head writer and founder of

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