How Many Forever Stamps for an International Letter?


March 9, 2024

Whether sending a letter to a U.S. address or outside the country, you must include postage stamps – those tiny, colorful squares you generally find stuck on the upper right corner of envelopes.

Beyond their decorative purpose, these stamps serve as proof that you’ve paid the cost of mailing your letter and ensure that carriers like the United States Postal Service (USPS) can deliver your mail safely and promptly.

However, if you’ve ever received a letter covered with postage stamps that make it look like a collage, you might wonder how many you need to stick onto an envelope when sending one.

The number of stamps you must stick onto a letter depends on the shipping costs; the higher the fee, the more stamps you need, mainly if you use stamps of lower denominations.

The use of the United States Postal Service’s Forever stamps aims to simplify this process by providing a one-stamp system for letters. The question is, “Does this apply to international letters?”

This article breaks down the intricacies of using Forever stamps for international letter postage, from what this specific stamp is and how it works.

For additional information on international postage, talk to a Postal Service representative. Find your area’s nearest post office using’s USPS facility finder tool.

What Forever Stamps Are Worth

Standard United States postage stamps come in various denominations, such as 1-cent, 5-cent, and 10-cent stamps. To send a letter at a postage rate of $1.00, for example, you must stick a $1.00 stamp or a combination of stamps with a combined value equal to $1.00.

Unfortunately, shipping costs can vary depending on your mailpiece’s weight, size, and shape. With international letters, the destination also impacts this fee, which means you must buy several stamps of various denominations to accommodate every possible postage amount.

Enter Forever stamps. Introduced by the United States Postal Service, also known as USPS and the U.S. Mail service, Forever stamps provide a convenient way for customers to pay their postage costs.

Unlike standard stamps, Forever stamps aren’t subject to price changes. Once you buy them, you can use them to send mail even if postage rates increase in the future. In contrast, the amount of postage a standard stamp covers decreases when shipping prices rise. 

The price of a Forever stamp is always equal to the value of sending a one-ounce letter through First-Class Mail. As of September 2023, this costs $0.66. 

In other words, if you’re sending a 1oz letter, you only use one postage stamp or one Forever stamp.

The Forever Stamp Program’s Success Is a Win for Everyone

A stamp will always have the value indicated on it. However, when shipping prices increase, a stamp loses value over time. To explain, let’s assume you bought a stamp with a $ 0.50 denomination.

If the postage rate to send a letter increases to $0.60, you’ll need a $0.50 stamp and an additional $0.10 stamp to cover the higher fee. With Forever stamps, you eliminate this problem.

In 2015, the U.S. Postal Service recognized the need for a more convenient and efficient postage solution. This realization led to the creation of Forever stamps for its other services.

Why Forever Stamps Are Great for Entering Sweepstakes

When USPS first introduced Forever stamps in 2007, their main purpose was to simplify and reduce the cost of sending letters through USPS’ First-Class Mail service.

However, these stamps aren’t limited to back-and-forth correspondence. 

You can also use them to protect yourself from rising postage costs and get better odds of winning when entering mail-in sweepstakes. Mail-in sweepstakes are raffles that let you participate by sending your entry via the U.S. Postal Service.

How Forever Stamps Work

Forever stamps are straightforward. You buy them, stick them to your envelopes, and drop your mail at your local post office or USPS mailbox. That’s it. 

A Forever stamp on your letters means you’ve paid the postage cost, regardless of whether that fee equals the cost of buying the stamp.

That said, one Forever stamp is only equivalent to the price of a one-ounce First-Class letter. Fortunately, the Postal Service offers Additional Ounce Forever stamps, which you can use for every subsequent ounce.

As of September 2023, an Additional Ounce Forever stamp covers $0.24. If, for example, you’re sending a 3oz First-Class letter, you must attach a Forever stamp plus two Additional Ounce Forever stamps to cover the postage rate.

Forever Stamps Don’t Last Forever

Although the value of Forever stamps is always tied to the price of mailing a 1oz letter through First-Class Mail, they can lose their worth if USPS’ sorting machines cannot read them.

Stocking up on Forever stamps is an excellent idea if you’re expecting shipping rates to increase. However, the U.S. Postal Service may not accept damaged Forever stamps. For this reason, you must store them in a secure location.

Can You Use a Normal Stamp for an International Letter?

You can use standard postage stamps to mail an international letter. You can also use Forever stamps. However, considering international shipping costs are generally higher than domestic ones, you’ll need to attach additional postage.

As of September 2023, sending a one-ounce letter through the Postal Service’s First-Class Mail International option costs $1.50. You’ll need two Forever stamps plus a stamp worth $0.18 ([$0.66 x 2 ] + $0.18 = $1.50) to cover the postage.

Fortunately, USPS has a solution- Global Forever stamps. Like domestic Forever stamps, Global Forever stamps are designed to maintain value despite price changes, making international correspondence more cost-efficient.

However, unlike domestic Forever stamps, the Global Forever stamps value is linked to the First-Class Mail International service’s shipping costs for 1oz letters.

How Many Stamps Do I Need to Send a Parcel?

The number of stamps you need to attach to your mail item, whether denominated or Forever, depends on the postage rate. This fee varies depending on the weight, size, shape, and country price group.

Country price groups refer to the shipping rates the U.S. Postal Service assigns each country. This system allows USPS to determine the postage costs for international shipments quickly.

Say you’re sending a 3oz letter to a country included in USPS’ 3-5 price group, such as Australia. Based on the Postal Service’s September 2023 pricing, the postage rate is $4.10.

In this scenario, you must attach one Global Forever stamp plus two Additional Ounce stamps, which equals $1.30 each, to cover the shipping cost ($1.50 + [$1.30 x 2] = $4.10.

On the other hand, let’s assume that you’re sending a parcel weighing 12oz to Mexico. At First-Class Mail International’s current postage prices, expect a shipping rate of $11.13.

For this example, you can use 16 domestic Forever stamps, worth $10.56 ($0.66 x 16 = $10.56), a $0.50 denominated stamp, a $0.04 stamp, and a $0.03 stamp ($10.56 + $0.50 + $0.04 + $0.03 = $11.13).

Note that you can use any combination of stamps to cover the postage costs. Although there’s no official limit on the number of stamps you can put on a mailpiece, you’ll be restricted on the amount of room your parcel has for postage. In short, the fewer stamps you use, the better.

How Many Stamps Do I Need to Send a Package to the U.S.?

Whether you’re sending mail to a U.S. address or an international one, the same rules apply. The number of postage stamps you must attach to a package depends on the shipping costs. 

Fortunately, the Postal Service can assist you in determining what this price is.

Calculating Postage at the Post Office

Various factors influence postage rates, from the item’s weight to the additional services you purchased to upgrade your package, such as insurance, signature confirmation, or USPS Tracking.

A Postal Service representative will provide you with the stamp price of your mailpiece when you visit a post office. You can easily find your area’s local post offices by visiting

Using a Postage Calculator

Alternatively, the U.S. Postal Service provides an online postage calculator tool, allowing you to determine the postage costs in the comfort of your home. This tool is highly beneficial if you want to avoid the hassle of visiting a post office and prefer USPS’ package pickup service.

You can find the USPS postage calculator by visiting the USPS website at You must identify your parcel’s size, weight, and class to use the tool accurately.

Can I Use Two Forever Stamps for International Mail?

You can use two domestic Forever stamps at the current postage price of sending a one-ounce letter via First-Class Mail International. However, you’ll need additional stamps worth $0.18 ($1.50 – [$0.66 x 2] = $0.18) to cover the $1.50 shipping fee.

Can I Use Three Forever Stamps for International Mail?

Three domestic Forever stamps equal $1.98 ($0.66 x 3 = $1.98), enough to pay for the current postage cost of shipping a 1oz letter through USPS’ First-Class Mail International service.

However, using three domestic Forever stamps means paying $0.48 ($1.98 – $1.50 = $0.48) more than one Global Forever stamp. While using domestic Forever stamps can be an alternative, it defeats the cost-effective purpose of Global Forever stamps.

What Happens if I Don’t Have the Right Amount of Stamps?

Unfortunately, mistakes in calculating the postage fee can happen, resulting in an incorrect number of stamps. USPS will still attempt to deliver your mail with a “Postage Due” notice when this happens.

This notice requires the recipient to cover the insufficient postage. If they don’t, the Postal Service may return the parcel to the return address. If there’s no return address, USPS will dispose of the mailpiece or open it to determine the return address.

If you’re using USPS international services outside of First-Class Mail International, such as Priority Mail International or Priority Mail Express International, USPS will still ship the package to meet the delivery deadline, but you must cover the insufficient postage.

However, if the mailing address is domestic, USPS will hold the mail item at a post office and contact you regarding the incorrect number of stamps. Delivery will resume once you’ve resolved the issue.

International Shipping Letter Postage

To give you an idea of how many postage stamps you must use to send a letter to an international address, here’s USPS’ September 2023 First-Class Mail International pricing:

Weight (oz)CanadaMexicoPrice Group 3-5Price Group 6-9

Countries in USPS’ 3-5 price group include Australia, France, and Spain. On the other hand, countries like Costa Rica, Nigeria, and the Philippines belong to price group 6-9.

For a comprehensive list of First-Class Mail International price groups, visit the USPS website. Alternatively, you can inquire with a Postal Service representative at your local post office, which you can find using’s USPS facility locator tool.

International Letter Shipping — USA to U.K.

The United Kingdom belongs to USPS’ First-Class Mail International Price Group 5. Based on the above table, the postage rate for a one-ounce letter to this destination is $1.50, which equals one Global Forever stamp. You must include one Additional Ounce stamp for every subsequent ounce.

International Letter Shipping — USA to Canada

If you’re mailing a letter to someone in Canada, expect more postage savings, as one Global Forever stamp covers up to two ounces when shipping to this country. However, you must attach Additional Ounce stamps when sending over 2oz.

Where to Buy Forever Stamps You Need and the Postage Costs

While Forever stamps are USPS products, other options exist besides the USPS website and post offices. You can buy stamps from various sources, such as online retailers, pharmacies, retail stores, and banks.

Note that Forever stamp prices can vary depending on where you buy it. For instance, a book of 20 Forever stamps costs $22.88, with each stamp costing $1.14 ($22.88 / 20 = $1.14). At the same time, a book of 20 Forever stamps from the USPS website only costs $13.20.


As of September 2023, the pricing for First-Class Mail shipping service is as follows:

First-Class Mail Letter (1oz)$0.66
First-Class Mail Letter Additional Ounce$0.24
Flats/Large Envelope (1oz)$1.35
Flats/Large Envelope Additional Ounce$0.24

Flat Rate Envelopes

Priority Mail and Express Flat Rate envelopes costs as of September 2023:

Priority Mail Flat Rate Envelope$9.65
Priority Mail Legal Flat Rate Envelope$9.95
Priority Mail Padded Flat Rate Envelope$10.40
Priority Mail Express Flat Rate Envelope$28.75
Priority Mail Express Legal Flat Rate Envelope$28.95
Priority Mail Express Padded Flat Rate Envelope$29.45

International Mail & Packages

Here’s the pricing for First-Class Mail International as of September 2023:

First-Class Mail International Letter (first ounce)$1.50
First-Class Mail International Flats/Large Envelope (first ounce)$3.00

Accuracy Notes

It’s essential to understand that all the postage rates discussed in this article are based on USPS’ September 2023 prices. However, these figures may change occasionally.

Therefore, you must watch for USPS services’ price changes. You can visit the USPS website for up-to-date information. 

Alternatively, you can contact a postal worker at your local post office. You can easily find USPS facilities using’s locator tool.

New Prices

Effective July 9, 2023, the cost of USPS mailing services increased by 2 cents. This change primarily affected the price of Forever stamps, raising it from $0.63 to $0.66. Other changes included the following:

ProductPrevious PricesNew Prices
Domestic postcards$0.48$0.51
International postcards$1.45$1.50
International 1oz letter$1.45$1.50

Previous Price Increases

Before the July 9, 2023 postage rate increase, USPS announced in October 2022 that effective January 22, 2023, it would raise the prices of domestic Forever stamps from $0.60 to $0.63 and Global Forever stamps from $1.40 to $1.45.

How to Save Money On Forever Stamps

If you’re a frequent sender of international mail, finding ways to save on postage costs can be beneficial. You can explore various postage options, bulk purchase discounts, or postage-saving tips from your local post office.

How Many Stamps per Ounce?

The number of postage stamps you must use per ounce of a standard letter depends on the stamps you’re using and whether you’re sending the mail within or outside the U.S.

For instance, sending a 1oz letter may require using multiple denominated stamps worth $0.66 when transmitting to a domestic address. You can achieve the same result by attaching one Forever stamp.

While you can still use domestic Forever stamps when sending a 1oz international letter, you may need two ($0.66 x 2 = $1.32) plus additional stamps equal to $0.18 to cover the $1.50 ($1.32 + $0.18 = $1.50) postage rate. Otherwise, you can use one Global Forever stamp.

Envelope Requirements: How to Weigh Your Envelope

With USPS’ Forever stamp system, sending letters to domestic and international addresses via First-Class Mail is cost-efficient. However, you must meet specific requirements to benefit from this service.

One of these guidelines is the envelope size. The maximum dimensions are 11 ½ inches by 6 ⅛ inches and ¼ inches thick. Another requirement is the weight, which must be below 3.5oz.

Consider buying a postage scale to ensure that your envelope meets USPS requirements. You can purchase them at a post office, the USPS website, or a local office supply store.

Sending More Than 3.5 Ounces to the United States or Sending Large Envelopes to the United States

If your mailpiece exceeds the envelope requirements, it may fall under the large envelope category, also known as flats. If your parcel is under 13oz for domestic and 15.99oz for international, you can still send it through USPS First-Class Mail.

Note that, like standard envelopes, large envelopes must follow specific size guidelines. The maximum size for large envelopes is 12 inches by 15 inches and ¾ inches thick.

If your envelope surpasses these limits, it will be subject to “package” postage rates. Thus, you must mail it through other USPS services, such as Priority Mail or Ground Advantage.

Send International Mail: Step-by-Step Instructions

Sending international mail involves several steps to ensure your letters or packages reach their destinations without problems. These steps include the following:

Ask, “Can I Send This?”

Before sending international mail, ensure that your parcel meets weight and size requirements. Additionally, you must check whether the contents of your mailpiece are permissible for international shipping.

Depending on the destination country’s regulations, certain items may be restricted or prohibited. Additionally, letters and flats must only contain documents and not goods.

For an in-depth look at what you can and cannot send internationally, visit the USPS website or talk to a postal worker. Head to to quickly locate the Postal Service’s facilities near you.

Choose Your Envelope or Postcard

As mentioned, you must comply with size and weight restrictions when sending mail to an international address with the Postal Service. However, selecting the appropriate envelope or postcard is also essential to protecting your mail and ensuring it arrives at its destination safely.

That said, if your parcel includes clasps, buttons, or strings, it may be subject to nonmachinable surcharges. These fees occur when postal workers must manually process a mail item.

Address Your Mail

Correctly formatting the sender and recipient addresses is crucial for successful international mail delivery. Fortunately, this process is straightforward. Here are the steps:

  • Write your name and address information in the top left corner of the envelope. Ensure that you include “USA” on the last line.
  • Write the receiver’s information, including their name and mailing address, in the center of the envelope. Put the destination country on the last line.

International Address Format Tips

Unfortunately, international address formats can vary wildly depending on the country. To simplify the process, write the delivery address in English.

You may write the recipient’s address in the destination country’s language if necessary. However, ensure that you provide the English translation.

Write Sender Address

To address an envelope, write your full name or company name and your apartment or suite number on the following line, then the street address, city, state, ZIP code, and “USA.”

An adequately addressed enveloped should look like this:

Write Delivery Address

At the bottom center of the envelope, write the recipient’s full name, followed by their street address, city, state, ZIP code, and country.

The recipient’s mailing information should look similar to this:

Calculate & Apply Postage

Once your mail is addressed correctly, the next step is to calculate and apply the postage. If your envelope weighs 1oz or less, you can stick one Global Forever stamp on the upper right corner.

A Better Way to Manage Shipping Costs

Calculating international postage costs can be complex, considering that the destination can influence pricing. Fortunately, you can use the USPS online postage calculator on its website.

Alternatively, you can request assistance from a Postal Service representative at a post office. You can visit to find your area’s most convenient USPS facilities.

Additional Postage

If your letter exceeds 1oz, you can purchase additional postage to meet the required rate. You can add postage up to 3.5oz for letters. However, the value of Additional Ounce stamps depends on the destination country’s pricing group.

Extra Services

Depending on your needs, you can purchase extra services to increase security and add tracking for your international mail. These additional services can include return receipts, certificates of mailing, and international insurance.

Note that any add-on services you want to be included with your mailpiece will increase the postage costs. In other words, you may need to stick more stamps to cover these surcharges.

Send Your Mail

The last step to ship mail to an international address is to send it. Fortunately, you have various options, including putting the parcel in your mailbox, dropping it off at a USPS collection box, or bringing it to your local post office.

Delivery Times for Letters to the United States

When you send a domestic letter through First-Class Mail, expect delivery between the next day and five business days. Delivery varies for international letters but is usually around 7 to 21 days.

Domestic Postcard Shipping

You can ship postcards via USPS’ First-Class Mail service. Like letters, the Postal Service provides a postage stamp option for postcards – the aptly named Postcard stamp. As of September 2023, this stamp covers $0.51.

COVID-19 / Coronavirus Status: Delivering Normally

During the COVID-19 pandemic, the USPS experienced a decline in its on-time performance. First-Class Mail’s effectiveness, in particular, decreased by 5% between 2019 and 2020.

Fortunately, the U.S. Postal Service is now delivering normally. It boasts a 91.5% on-time delivery rate for First-Class Mail. USPS aims to deliver your letters to their intended destination safely and promptly.


  1. How much is a stamp for a letter in Australia?

The postage rate for mailing a 1oz letter to Australia via First-Class Mail International is $1.50. A Global Forever stamp costs $1.50, as its value is tied to the service.

  1. Do international letters need two stamps?

Whether you need two stamps for an international letter depends on the weight, destination, and stamp you’ll use. For instance, sending a 1oz letter to Canada, the postage rate is $1.50.

Using domestic Forever stamps, you’ll need two ($0.66 x 2 = $1.32) plus additional stamps worth $0.18 ($1.50 – $1.32 = $0.18). However, you’ll only need one Global Forever stamp to cover the same shipping costs.

If you’re sending a 2oz letter to Mexico, sticking one Global Forever stamp may not be enough, as the postage fee is $2.27. While using two Global Forever stamps ($1.50 x 2 = $3.00) will suffice, you’ll overpay $0.73 ($3.00 – $2.27 = $0.73).

  1. How many stamps do I need to send a letter?

The number of postage stamps you must attach to your letter varies depending on the weight, size, destination, and included extra services.

  1. How many stamps are in a book?

A standard book of stamps includes 20 stamps. However, you can also buy a stamp coil or roll containing 100 stamps.

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

A 9-inch by 12-inch envelope means you’re shipping a large envelope. You’ll need two domestic Forever stamps and a 3-cent stamp to cover the $1.35 ([$0.66 x 2] + $0.03 = $1.35) postage rate. However, that’s assuming the envelope only weighs one ounce.

If your envelope weighs more, you must purchase Additional Ounce stamps for every subsequent ounce or add a $0.24 stamp.

  1. How many stamps do I need for an international postcard?

To send a postcard to an international address, you need a Global Forever stamp, as the postcard shipping rate is $1.50 for all countries. 

  1. Can I use old stamps in Australia?

Postage stamps are worth their denominated value. While they cover less as shipping prices increase, you can still use old stamps as they never expire. That said, the usability of old, damaged stamps is subject to the carrier’s discretion.

  1. Do you need special postage for international mail?

You can use domestic Forever stamps to cover the postage of international mail. Alternatively, you can use Global Forever stamps, the postage stamps designed explicitly for First-Class Mail International.

  1. How many stamps are for a postcard?

Again, depending on the stamp you’ll use, a postcard may require one Postcard stamp or a combination of denominated stamps.

  1. Where should I apply stamps on a letter?

You don’t apply the postage stamp on your letters. Instead, you stick it onto the upper right corner of the letter’s envelope.

  1. How many stamps do I need for a large envelope (flats) to the United States?

The number of stamps required for sending large envelopes or flats varies. For instance, mailing a 2oz flat costs $1.59 and may require you to attach three Forever stamps ($0.66 x 3 = $1.98).

However, you can also cover the same $1.50 postage cost using a different combination. For example, you can use two Forever stamps ($0.66 x 3 = $1.32) plus a collection of stamps valued at $0.27 ($1.59 – $1.32 = $0.27).

  1. Can I print an international stamp?

With USPS’ Click-N-Ship, you can print international shipping labels with postage. For more information on Click-N-Ship, you can visit the USPS website or a local post office location. You can find Postal Service facilities easily with’s locator tool.

  1. How much does it cost to post a card to England from Australia?

As of September 2023, it will cost you $3.00 to ship a greeting card from Australia to Europe.

  1. Can I use normal stamps for international mail in Australia?

If you’re in Australia, you can use domestic stamps to pay the postage for international mail. However, you must include an additional 10% of the shipping rate.


  1. How to Send a Letter or Postcard: International
  2. US Stamps by Denomination
  3. Forever Stamp Fact Sheet
  4. First-Class Mail
  5. What To Do With Unused Stamps
  6. Forever Stamps: What They Are and How They Work
  7. Postage Stamps – The Basics
  8. USPS Price List
  9. First-Class Mail International
  10. Insurance & Extra Services
  11. Retail Postage Price Calculator
  12. Schedule a Pickup
  13. What Happens if I Didn’t Put Enough Postage?
  14. U.S. Postal Service Files Notice with PRC for New Mailing Services Pricing
  15. First-Class Mail Fact Sheet
  16. What is the Non-Machinable Surcharge for First-Class Mail®?
  17. How Many Stamps Do I Need?
  18. U.S. Postal Service
  19. Service Performance Remains Steady Across Postal Service Network
  20. Postage Options