How Many Stamps Do I Need to Send a Letter within the US

How Many Stamps Do I Need?

This question is quite confusing for those who do not use post services regularly. However, a significant majority sends and receives parcels, posts, and packages worldwide.

Every postal service has defined its pricing features and other regulations to facilitate the sender and receiver.

How Many Stamps Do I Need?

This article will elaborate you the number of stamps for standard letters, one-ounce letters, small packages, large envelopes, flat-shaped letters, and many others.

Additionally, you will read about virtual mailboxes, types of stamps, and United States Post Service (USPS) pricing features and requirements to send mail.    

Virtual Mailbox for your Postal Mail-A Better way to Manage Mail

Virtual Mailbox offers services for your postal mail. It is the most trending mail service these days. Receiving or collecting mail often becomes complicated when you are not at home.

Who will receive your postal mail? Sometimes, people receive a mail and forget to open it due to a busy routine. Virtual mailbox has set all for you. It is a superb mail service.

How does it work?

It works simply. Follow 3 –step procedure as given:

  1. You need to choose a package of the organization offering Virtual mail services. Choose a monthly package and add the delivery address of the selected virtual box in collaboration with USPS. Read about the awaiting delivery scan. You will fill a consent form that reveals the consent of USPS and the sender to receive and handle the mails. This consent prevents the misuse of the received mails.
  2. When you change your home or business postal address to the virtual box, the selected virtual box starts collecting mails for you. Many virtual box apps and web services are available online. Choose the best premium package that suits you.
  3. Last but not least, log in to your virtual box and choose what to do with your mails. If you want, the virtual box will collect all mails for you and will send on another address wherever you want in the world. This feature suits professional travelers. Further, a virtual box can open and scan your letter and show you in Pdf r image format.

Core features

  1. Virtual mailbox stores your mail for 30 days. If you want to extend it, choose another monthly premium package.
  2. It prioritizes privacy and confidentiality. All your scanned mail is downloaded directly into your virtual mailbox. No one can open or check it without your permission.
  3. Virtual mailbox services locally collect and store your letters and envelopes. You can anytime walk in, and check out at the said locations.
  4. If the receiver does not want to store the physical letters and envelopes, choose to recycle them. Your postal mails will not get stored in the specified locations. Instead, Virtual mailbox services will recycle your mail securely and environment-friendly way.

A virtual mailbox is an ideal way to manage your business or personal mail.

Online companies find it much convenient to receive all business-related mail into a virtual mailbox.

Check your postal mails anywhere, anytime, without worrying about receiving postal services and ZIP codes.  

How many Stamps do I need to send letters within the United States?

Several stamps depend upon the weight of the letter or mailing envelope. For a first-class flat letter, a single forever stamp is enough. United States Postal Service (USPS) issues stamps forever for first-class letters.

By January 2021, the rate of a forever stamp is $0.55. So, you need to pay only $0.55 for sending a letter within the United States.

If the first-class letter weighs equal to or less than 1 ounce, you will need only a single forever stamp. For each additional ounce, the sender pays $0.70.

If the letter weighs 2 ounces, the cost of postage stamp increases to $0.75. For a 3-ounces letter, the sender pays $0.85.

USPS has fixed some regulations for sending a first-class letter within the US like:

  • The paper size should be A4.
  • A 1-ounce first-class letter should not exceed more than four pages.
  • The letter should be folded in two folds only in a rectangular envelope.

On using a square shape envelope, you need to pay extra charges. However, the general public sends first-class mail with one forever stamp within the United States.

You need two Domestic Forever Stamps. This, as you know, equals $1. However, this is just for the first ounce. You have to purchase more stamps for every ounce above that weight

How many Stamps for a Postcard?

Sending a postcard within the United States is quite economical. For a postcard, just purchase a postcard stamp costing $0.35 only.

Or, if you have already purchased a forever stamp, you can send your postcard pasting the first-class forever stamp. But it is a bit expensive.

Why would one pay extra for a postcard, when there is a cheaper option available? Many people do so due to a lack of postcard stamps literacy. 

To qualify for a $0.35 postcard stamp, your postcard stamp must meet the following features:

Size & Dimensions of the postcard

For a postage rate with a base price of $0.35 stamp, the sender needs to follow the given requirements:

The height should be at least 3.5 to 4.25 inches.

The length of the postcard can be 5 to 6 inches.

The uniform thickness should range between 0.007 to 0.016 inches.


The shape of a postcard should be rectangular. If it is non-rectangular or square-shaped, you will be charged $0.21 extra. Thus with a $0.35 postage stamp, you will pay $0.21.

It makes the total cost of the postcard up to $0.56 approximately. 


The cost of postage increases per ounce. For a 1 ounce postcard, the postage price is $0.35. On increasing the weight of the postcard, the mail clerk will ask you to pay extra charges as well.

The given dimensions and features make the correct postage for a first-class postcard. If the postcard exceeds the given features, the sender has to pay extra charges.

The sender should mention the valid return address to complete the mailing process. Otherwise, mail will be sent back to the sender or the post office. 

How to Weigh your Envelope and Envelope Requirements

USPS has set specific regulations for the envelope’s weight and other features. Have a look at:

  • Envelope weight

The weight of the envelope should not exceed 3.5 ounces. The first-class mail with standard size carries a 1-ounce letter. For increasing the weight, the sender pays for each ounce.

The flat rate price of a 1-ounce letter is $0.55. For each additional ounce, the sender pays $0.20. Thus, a letter of 2 ounces costs $0.75, a 3-ounce letter costs $0.95, and so on.

  • Envelope size

For first-class letters, the specific height, width, length, and thickness features are fixed. If the letter size increases than the given features, the letter sender pays extra charges for it.

  • Machinable vs. non-machinable

If the dimensions of your letter are according to the instructions of USPS, the letter is machinable. It means that your letter or envelope can go through a machine and can pass one of the mail orientation procedures.

For instance, all rectangular, flat letters with given dimensions are machinable.

The letters that the machine cannot pass have to sort manually. Which letters are non-machinable?

The square, large envelopes, rigid envelopes, envelopes with soft material, and extra folds of letters make it non-machinable. Dedicated representatives at the post office sort out such envelopes by hand.   

  • Large envelopes & mails

Large envelopes with flat first-class letters may cost you $1 or more than that. It depends upon the case. Large fluffy packages or parcels may cost you up to $4.

However, a postage calculator can do all for you. It will calculate, weight, size, shape, and cost of your mailing envelope. 

Different Types of Stamps

US postal services use many types of postage stamps. These stamps are categorized as under:

Definitive Stamps

USPS issues millions of definitive stamps every year. These are printed in larger quantities. You will find definitive stamps worth 2 cents, 55 cents, $5, and many others.

Definitive stamps may include the images of the US flag, folk prestige household items, national symbols, and many others.  

Forever Stamps

Forever stamps are first-class stamps. It is commonly used for first-class mail. Its starting price is 55 cents. US postal services started printing the forever stamps in 2007.

The forever stamps are the best ones for mailing a letter that weighs less than 1 ounce. The purpose of printing a forever stamp was to use it whenever the user wanted a particular feature of the forever stamp.

 If a user purchases it and does not use it for years, its worth will not decrease. Even if the cost of a forever stamp gets increased to some cents, the user can use it to mail letters.

If you purchased a forever stamp that costs $0.46, what will you do if its cost increases after one year? You can surely use this low-cost forever stamp still. These are evergreen stamps.   

types of stamps

Commemorative Stamps

Commemorative stamps are printed to celebrate the memories of persons, places, events, and anniversaries.

Commemorative stamps issued in 2021 includes sun science- revealing the latest experiments on the sun, the Star Wars, Droid-the scientist’s efforts to approach stars and planets, Chien Shiung-a popular Japanese personality, etc. 

Another attractive commemorative stamp includes “Go for Broke: Japanese American Soldiers of WWII.” These stamps are issued in the memory of Japanese and American soldiers who were martyred in WWII.

The Lunar New Year; the Ox Year is another eye-catching stamp that memorizes and celebrates the New Year.

Semi-postal Stamps

USPS sells semi-postal stamps at premium rates. The purpose is to collect funds for funding agencies. USPS sells semi-postal stamps at a bit higher rates.

Later on, after deducting the cost of a mail, the rest of the amount is transferred to the administrative funding agency. That agency sends the funds to the dedicated body.

In 1998, semi-postal stamps for the breast cancer cause were distributed. These postal stamps are yet available for the cause of breast cancer.

Similarly, the “heroes of 2001” were issued in 2002-2003 to fund the families of World Trade Center destruction victims. From 2011 till now, fish and wildlife services collected funds f $1.74 million by printing the stamps on extinct animals or rare animals.

How Many Stamps Do I Need for a Letter per Oz?

A standard letter per oz. It may cost you $0.55 only. The flat rate envelope may vary as per the type of package you choose. Like, the extra postage depends upon the destination country and additional options.

Calculating the Weight and Cost of Your Mail Item

Other than USPS, United Parcel Service and FedEx are authorized to deal with Mail items.

The postage calculator calculates the weight of the posting items. You need to measure envelopes or packages and enter the dimensions in the online postage price calculator to get a start. 

It is convenient to know the postage stamp rates as per mail types and mail handler. Every mail handler has different rates of regular stamps and unique stamps for the standard and larger envelope.  

How to Calculate the Cost of the Postal item? 

Open a shipping calculator. Enter the height, width, and length of your parcel. It will show the dimensional weight of the parcel in the lbs. now, you can assess what type of stamp and how many stamps are required for your parcel.

You may have to enter the postal code, shipping address, return address, and other details for accurate calculation.  

You may go to the USPS official website and click on the “calculate a price” in the drop-down menu. A pricing calculator will get opened.

All you do is fill in all necessary features like mailing code, zip code, postal code, country, or state, and choose the type of envelope you want to send. After filling in all requirements, you will see the total cost of your mailing item.

How Many Stamps Do You Need for International Mail?

USPS delivers posts to nearly 190 countries. It charges the shipping cost, including a shipping label, stamps per ounce, the maximum weight of the package, destination country, and package you choose.

If is goes out for delivery or shows this type if error after sending then

Priority Mail and Priority Mail Express features different stamp packages with shipping options.

The number of stamps may vary as per the International mail package you choose. Let us have a look at the mailing packages authorized by USPS:

Global Express Guaranteed

Global Express Guaranteed is the service that ensures the fastest delivery worldwide. Your mail package will get received within 1 to 3 business days. USPS claims that no postal service is as fast as Global Express Guaranteed is.


  • It includes the insurance of $100.
  • You may track your parcel at all destination countries all the time.
  • The unique feature of the package is that you can send your parcel on a specified date to your friends and families. In case of poor or non-compatible service, you will get back your money.

The lowest mail package price in the guaranteed package is $67.80. The prices vary as per weight, size, shape, and distance of the delivery address.

However, the maximum weight allowed is 70 lbs while the length should not exceed 45 inches, height than 46 inches, and width than 35 inches.

Changes in size can lead to additional postage, or your package may get out of the flat rate box limit. 

Priority Mail Express International

Priority Mail Express International is an affordable post service with faster delivery. The post prices start at $45.95.


  • It delivers mail within 3 to 5 business days.
  • It features free-package pick up from home or office.
  • The maximum weight allowed is 70 lbs. per mailbox, while flat envelope weight is up to 4 lbs.
  • It also offers money-back guaranteed services to the destination countries.
  • It includes $100 or $200 insurance. Several conditions apply.
  • The one-price package with a weight of up to 4lbs. is a great feature. Pay fixed amount at flat rate envelope up to the mentioned weight.

However, the price of the package may increase as per the weight and delivery destination you choose. 

Priority Mail International

Priority Mail International delivers the packages and parcels within an affordable price range. Its lowest mail package starts from $28.50. However, the prices may vary as per weight, destination, and other requirements.


  • It delivers the envelopes and boxes within 6 to 10 business days securely.
  • You may track your parcel from the mailing address to the destination address.
  • It also includes insurance of $100 and $200 with specific terms and conditions.
  • It may include the free package pick-up delivery.
  • The maximum weight for the flat boxes is up to 70lbs, while the weight for flat envelopes is 4lbs.
  • Talking about packaging, the authorities accept the parcels that are enclosed in standard folds. 

First-Class Mail International

It is the most commonly used service to send letters and envelopes worldwide.


  • You can send 1 oz. Letters and flat envelopes with one Global forever stamp. The cost of a global forever stamp is $1.20. Another option is that you can send your mail by using two regular forever stamps. The appealing thing is that these stamps never expire. Even you can use them after years. If the price of the USPS stamps fluctuates, it does not affect the worth of an older forever stamp.   
  • It is the most affordable and popular postal package.
  • It delivers flat letters and postcards up to 3.5 oz. and flat boxes up to 15.9 oz.
  • The mail sender has to pay extra charges for larger mail pieces or envelopes. other than regular size charge the mail sender cost of ex.

First-Class Package International Service

It is among the most affordable and economical mail services for international mail senders and receivers. The package starts at the fantastic price of $14.25.

The maximum weight allowed is 4lbs. Further, the package value should be less than $400. Many other terms and conditions apply. Certain countries impose restrictions and prohibition regulations as well.

Airmail M-Bags

Airmail M-bags offer deliveries of printed materials in more significant amounts. For instance, you can mail magazines, newspapers, publishing material, and other printed material securely t other states.

The M-bags are specified for sending documents of 11lbs. the maximum weight allowed is 66 lbs. the starting mail price is $51.70. The deliveries are provided at the post office of the area. 

Where to apply Stamps on a letter?

Usually, stamps are pasted on the top right corner of the envelope. If you use a sticker-based stamp class, remove the paper from the back and paste the stamp. If you are using a simple stamp, apply glue at the back of the stamp, and paste it.

The purpose of pasting the letter stamp in the top right corner is logical. It can easily get scanned and processed by the mail scanning instrument.

Sometimes, people and mailing companies use to paste the stamps at the top-left corner as a mailing label. The street address of the receiver is mentioned just adjacent to the stamp.

Make sure that the stamp would not overlap the sender or receiver’s standard address. Both addresses should be written clearly on the envelope.

Apply the adhesive stamps as per stamp rules, so there will be no issue with the postage and delivery. It lets mail carriers deliver International first-class mail at its correct destination. 

Where to apply stamps on a letter?

How Many Stamps Do I Need Per Ounce (Oz) of Mail?

It requires nearly one forever stamp for a per ounce mail. As the weight of the mail increases, the cost of the stamp also increases. For each additional ounce, the mail sender needs to pay $0.20.

How Many Stamps Do I Need To Mail a Card?

You need only one stamp worth $0.35. Mailing a postcard is a cheaper and quicker way to wish your friends, family, and loved ones. The rate of $0.35 applies for a postcard of one ounce.

For additional ounces, you will have to pay $0.20 cents per ounce.

How many stamps do I need for a large envelope?

Large envelopes have the exact postal requirements as standard-sized or other flat envelopes. A standard size envelope requires a forever stamp of $0.55.

But oversized envelopes or legal-size envelopes may cost you $1.0 or more on unique stamps depending on weight. The legal size envelopes require two forever stamps, each of $0.55 value.

Alternatively, you can opt for a single stamp of value $1.00 that is more affordable. This rate is for a 1-ounce letter. The sender has to pay the extra charges for the envelope of more than 3.5 ounces.

How many stamps do I need for a 9×12 envelope?

A 1-ounce 9×12 envelope needs two forever stamps worth $1. If you are going to send 9×12 padded envelopes for international posts, the cost of stamps will vary as per USPS international mail regulations.

For a standard 1-ounce 9×12 envelope, you will have to purchase two forever stamps. Many people like to purchase more convenient stamp books.

Moreover, if your 9×12 envelope weighs 2-ounces, you will have to pay $0.20 for an additional ounce. Thus, it makes a total cost of $1.20. Normally, the number of stamps or their cost depends on the types of envelopes as well. 

What Happens if you Put too many Stamps on an Envelope?

Yes, you may put as many stamps as you want. Each stamp costs some value. You will have to pay extra money on adding extra stamps to an envelope.

The reason is simple. Each stamp costs some value. For all additional stamps, you have to pay the authorities as per the current price.

Why will someone like to add extra stamps? Some may like to paste stamps. This likeness may lead to adding extra stamps. Others may have purchased extra stamps already, like stamp books.

It automatically increases the mailing cost and letter prices as well. Whatever the case, the post office does not refund you the number of extra stamps.

Additional stamps are allowed, but the mail receiver has to suffer and pay charges in case of insufficient postage.

When you are sending additional items of heavier items that do not comply with the package details, then you need to add more stamps. Adding more stamps to your nonmachinable items will not cause them a quick delivery. 

What Happens if you Put too many Stamps on an Envelope?

Final Words: How Many Stamps do I need?

USPS is an affordable and reliable postal service for domestic and all types of mail. If you are confused yet about the types and quantity of stamps, get relaxed.

It may not seem easy to you in the description, but the procedure is quite easier. When you go to the post office in person, the front-desk officer will see your mail and guide you about the stamps.

Further, the officer can better guide you about the cost of your mail or package and the correct option. USPS has fixed specific shapes, dimensions, sizes, and weight of the mail items.

Just be sure of what you are sending, whether paper items, greeting cards, birthday cards, vertical envelopes, or packages.

Add the shipping addresses carefully so you will get the items delivered to the right places. Remember, you need to get delivery confirmation receipts as proof of delivery will. Postage stamps are not delivery proof at all. 

For pricing features and other details, go to the official website of USPS and collect the required information.

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