How Many Stamps Should i Put On A 9×12 Envelope in 2023

Most times, you need just ONE stamp to send a letter with the right value using the 9×12 envelope. But the cost of the postage widely depends on your location and the destination of the letter.

In any case, you’ll get the exact information from your nearest post office. For business purposes, using stamps on an envelope is just an emergency effort. While going through metered postage, reduces the delays of delivering the letter and protects you from underpay or overpay of stamps.

Thus, it offers the business the way the professionals do. That means the size and weight determine the correct value of the postage when you send mail using stamps. Well, let’s know a bit more in reply to the question; “how many stamps should I put on a 9×12 envelope?”

How Much Does It Cost To Send A 9×12 Envelope?

Apart from the number of stamps you need to use on a 9×12 envelope, it’s also crucial to know the costs that are associated with it. With the starting price of $1, the cost depends on your envelope’s weight and every additional ounce costs $0.21.

If you want to send this type of big envelope, you don’t have to visit any post office if you have enough stamps. Also, you can avoid going to a post office if you have the right to enter print, online postage stamps, or a postage meter from any company.

For the type of “Priority Mail Flat Rate” the rates of postage are going to increase from 2022 and will cost $7.75, which is currently 7.55. That means it’ll increase by about $0.20 from next year.

Besides, the type of “Priority Mail Medium Flat Rate Box” will increase by $0.40 that will be $13.20, which is $12.80 currently.

We have an in-depth article about the cost to mail a 9×12 envelope, please read it for a better knowledge of mail sending cost

How To Buy Postage Stamps for Large Type of Envelope?

Large types of envelopes include a 9×12 envelope along with manila envelopes and oversized cards. Also, other large types of envelopes are large but light in weight mailers. These include brochures and flats that are First-Class mail in the category.

This type of letter costs $1 for a single-ounce mailing from January 2022. The maximum is 13 ounces costing $3.40, which is the highest weight for this mail (First-Class). Frequent use of the First-Class stamp will cost you $0.55.

So, if you want to ship a mail per one ounce of weight, it’ll take 7 standard stamps for a package that weighs 13 ounces. In this case, for every single ounce of additional weight, it’ll cost another $0.20

How Many Stamps Do I Need Per Ounce?

When you need to ship a bulkier mail, you can avoid using two Forever Stamps on it. Because of the more massive letter, you’ll enjoy a cheap cost. The cost is just $0.15 for every single ounce of extra weight. You can do it as a replacement for $0.55 for a letter of one ounce.

You can pay $0.70 for a product when you include two ounces of the letter with two Forever Stamps. While sending a single-ounce letter in the US, you can ideally use the Forever Stamps for posting normal-sized envelopes.

You should weigh your letter before you affix a stamp if you suspect it may have a higher weight. It’s because letters with heavier envelopes will get back as a result of postage lack. So, you should add the required postage with enough stamps to confirm the delivery of the mail.

How Much Postage do I Need for a 9×12 Envelope?

The cost of postage for a 9×12 envelope, which is a large 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.

The number of stamps needed for a 9×12 envelope depends on the weight per ounce. So, you need two stamps for one ounce of the 9×12 envelope. And the cost of two stamps costs $1.10 which is $0.55 per ounce.

The United States Postal Service classifies a 9×12 envelope as a flat. The postage required for mailing a 1-ounce flat is $1 for the first ounce and $0.20 for each additional ounce. So, the total postage required to mail a 4-ounce envelope will be around $1.60.

The answer to the question; how many stamps do I need for a 4 oz 9×12 envelope is 3. And that of how many stamps do I need for a 5-ounce 9×12 envelope is 4.

How Many Stamps Do I Need for a Manila Envelope 9×12?

The manila envelope is a large envelope and you would need two stamps for it. The cost required for the first ounce is $1.00 and $0.20 for each additional ounce. The cost of stamps is $0.55 each.

How Many Stamps Do I Need for a Large Yellow Envelope?

You might be wondering how many stamps does a yellow envelope need. The answer to that question is two. A large yellow envelope needs two standard stamps.

Does the Size of an Envelope Affect Postage Cost?

The shape and size of an envelope affect the cost of postage.  Postage prices vary from postcards, letters, large envelopes (flats) to parcels. Generally, the bigger your mailpiece, the higher it will cost to mail. In First-Class Mail, postcards are less expensive than letters.

Frequently Asked Questions

  1. How Long Does it Take a Mail To Be Delivered?

    Generally, a standard mail takes about 3 to 4 days for it to be delivered, while a priority mail takes 1 to 3 days, and priority express mail takes 1 to 2 days.

  2. Can I Mail a Black Envelope?

    The answer is yes. Post offices accept and mail black envelopes provided the print is legible and there’s enough contrast between the dark background and print.

  3. Can I add Stickers To My Envelope?

    Yes, you can. Just ensure that the stickers are not too close to areas where the address will be stated. Also,  don’t put a sticker where the stamp goes.

  4. Can I Mail a Letter Without a Stamp?

    No, you can’t. Any item mailed without a stamp will be returned to the sender if a valid return address was written on the envelope.

  5. Can I Mail a Letter For Free?

    No, you can’t. In most countries, regular-sized letters or postcards cost a minimal fee to mail. This fee is represented by a postage stamp, which can be purchased from your local post office.


When sending a mail, ensure that the envelope is properly packaged, stamped, and addressed. The stamp should be placed at the top right-hand corner of your envelope. The destination address, which is who are you sending the letter to should also be written legibly.

The envelope should be well sealed before proceeding to mail it. Mailing your stamped envelope or postcard is quite easy. All you need to do is leave it for your mail carrier to pick up or drop it off in several locations like dropping it off in a blue collection box or taking it to a post office.

2 thoughts on “How Many Stamps Should i Put On A 9×12 Envelope in 2023”

    • i have a large envelope with 4 pieces of paper i need to send. so simple but you people just refuse to have anything on what people actually need to know. go to the post office, stand in line for half an hour. why expect a simple answer? i transfered to a simple letter envelope and stuck 2 stamps on it. i see why the doctor refused to mail it, because you people refuse to have simple answer, i had to drive 30 miles round trip to pick this up. was not going to post office on top of an already STUPID endauvour.


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