The cost is just $0.98 or two Forever Stamps if you want to send just paper inside of a 9×12 envelope. But, the thickness of the envelope should be uniform and it should be bendable as well. Also, you have to pay $0.21 for every additional ounce up to 13oz in total from April 2022.
However, some things may be considered as a package or letter that is non-machineable with $0.20 for each ounce. So, the cost varies depending on the weight, as well as the distance of the person it’d be delivered to.
If you send something that is equal to or less than one ounce, it’ll cost you a minimum of $1. From last January 2021, the cost of each additional ounce or its part has changed and has become a bit more expensive than its previous cost.
Let’s get to know a bit more about the topic “how much does it cost to mail a 9×12 envelope.”
How Many Stamps Must I Put On a 9×12 Envelope?
We mentioned earlier that the cost of the postage for a large envelope of 9×12 size has changed. The first ounce of a 9×12 envelope should use two Forever Stamps (equivalent to $1). Besides, you have to pay the extra stamps for each additional ounce which is equivalent to $0.20.
But, this charge is only applicable if the envelope is equal to or less than 3/4-inch thick and is not rigid. As described before, the total postage of this type of envelope might be $1.40.
Any mixture of denominating stamps equivalent to the corresponding amount can be used. So, it can cover the required postage while using the ubiquitous Forever Stamps for every three $.55.
However, you may need to overpay by a quarter of a dollar which is about $.25. Therefore, four postcard stamps of $.25 each will result in the full exact amount of postage it needs if you get them readily on hand.
What are the Costs of the Large Envelopes to Send Mail?
The large envelopes are also well-known as “Flat Mail” It is also referred to as “First Class Mail.” The mail is 6⅛-inch in height, 11½-inch in width, and ¼-inch in thickness. When it comes to the large envelopes, they usually come with marketing newsletters, legal correspondences, and product catalogs.
Also, they could comprise books, CDs, magazines, manuscripts, reports, and some other types of documents. The mails should be uniform in their initial stage without being folded or bent.
Typically, these types of envelopes fit a sheet of paper of 8½-inch x 11-inch. But, you can’t send mail with 12-inch height, 15-inch width, and ¾-inch thickness in terms of a large letter.
Moreover, the weight of the envelope should not be more than 13 ounces. If it’s more than the said weight, the USPS will consider it as a parcel. And you’ll have to pay as per the parcel prices.
Why Should I Send Mail Through the Large Envelopes?
You’ll never need to waste time at the Post Office again if you understand the simplicity of sending large envelopes. It’s possible with the help of some others rather than the post office like an online service provider.
They can tell you accurately the number of postage you need and how much to mail a large envelope which is the amount of money you need to send the mail. Also, they can help you print officials; the government-approved postage, and address levels from your office or home.
Besides, they also allow you to complete the customer forms through their organizations. Thus, it helps you to print your address, postage, and customer forms with ease.
Postage for a Large Envelope
You’re probably wondering how much large envelope postage costs. You have your answer here. Large types of envelopes include a 9×12 envelope together with manila envelopes and oversized cards. There are other large types of envelopes that are, however, light in weight. These include brochures and flats that are categorized as First-Class mail.
The postage rate for a 9×12 envelope which is a large envelope is $1 for a single-ounce mailing. The maximum weight of postage for a 9×12 envelope is 13 ounces and it costs $3.40. This is the highest weight for this mail (First-Class.
9×12 Envelope Postage Rates
The cost to mail a 9×12 envelope is $1.00 for the first ounce & $.20 for every additional ounce provided that the item is less than a quarter-inch thick and is not rigid.
USPS Large Envelope Rate
The United States Postal Service classifies a 9×12 envelope as a large envelope. The postage for a 9×12 envelope of 1-ounce flat weight is $1 for the first ounce and $0.20 for every subsequent ounce.
Pricing Table About Postal Rates 2022
Type of Mail | Prices ($) |
Letters (1 ounce) | 0.58 |
Letters, Additional ounce(s) | 0.20 |
Letters (metered 1 ounce) | 0.53 |
Domestic postcards | 0.40 |
Flats (1 ounce) | 1.16 |
Outbound International Letters | 1.30 |
What is the weight of a large envelope?
A typical envelope weighs 6.75 grams. Since a sheet of paper weighs 4.5 grams, a typical letter weighs at least 11.25 grams. This is equivalent to 0.238 ounces for the weight of the envelope and 0.159 ounces for the weight of the paper resulting in a total weight of 0.397 ounces.
What is a First Class mail?
First-Class Mail service is an affordable and easy way to send envelopes and lightweight packages. First-Class Mail Forever stamps cost $0.58 (the current price for 1 oz) and will never expire, even if the First-Class postage rate goes up. For packages (up to 13 oz), prices begin from $4.30.
What is the maximum weight and required shape for a first class mail?
The maximum weight for a First-Class Mail letter is 3.5 ounces while for large First-Class Mail envelopes and parcels, the maximum weight is 13 ounces. All postcards and envelopes (or flats) must be rectangular in shape, otherwise, an additional charge may apply.
What are Non-machinable Envelopes?
Non-machinable envelopes refer to unusually shaped mail, like square or vertical envelopes, lumpy envelopes, rigid envelopes. They are charged a nonmachinable surcharge even if they weigh less than 1 ounce. Mails with clasps, string, or buttons must be hand-cancelled.
What happens if a mailpiece is too big?
If a mailpiece exceeds the maximum length, height, or thickness, it will be charged at the next higher price and mailpiece category. Large First-Class envelopes (flats) that exceed maximum dimensions, are rigid, non-rectangular, or not uniformly thick, are charged with parcel prices.

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