How Much Postage for Square Envelope ?

When it comes to mailing a square envelope, you must be aware of the postage requirements to ensure that your envelope arrives at its intended destination without any delays or additional fees.

First, it’s important to note that square envelopes are considered non-standard mail by the United States Postal Service (USPS). This means that they may require additional postage compared to standard rectangular envelopes.

To determine the correct postage for a square envelope, you must know its size and weight. The USPS uses a system of postage rates based on the dimensions and weight of the mailpiece, so it’s essential to have accurate measurements.

If your square envelope weighs less than 1 ounce and is no larger than 6.125 inches by 11.5 inches, you can use a standard First-Class Mail postage stamp. However, you may need additional postage if your envelope is larger or heavier.

For square envelopes larger than 6.125 inches by 11.5 inches or weighing more than 1 ounce, you will need to consult the USPS postage rate chart to determine the correct amount of postage. This chart is found on the USPS website or at your local post office.

It’s also worth noting that square envelopes may require additional handling fees, as they are not as easy to process through automated sorting machines as rectangular envelopes. To avoid these fees, consider using a standard rectangular envelope instead.

Below, we have mentioned some characteristics of Non-Machinable or Odd Sized Letters, which envelopes mainly used for advertising, Greeting cards, and invitations.

Characteristics of Non-Machinable or Odd-Sized Letters:

  •     Square type envelops
  •     Rigid Envelopes
  •     Lumpy Type Envelopes
  •     Envelopes wall thickness more than 1/4″ 
  •     Vertical Type envelopes
  •     Envelops that have strings and clasps

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Square Envelope Sizes:

Envelope TypeSize in InchesSize in Millimeter
5 Square5 x 5127 x 127
5 1/2 Square5.5 x 5.5140 x 140
6 Square6 x 6152 x 152
6 1/2 Square6.5 x 6.5165 x 165
7 Square7 x 7178 x 178
7 1/2 Square7.5 x 7.5190 x 190

How Much Does It Cost to Send A Square Envelope?

The cost of sending a square envelope will depend on several factors, including its dimensions (including thickness), weight, origin and destination, and the level of service required.

The standard postage rate for Square, oversized, or unusually shaped envelope stamps start at $1.03.

Unusually shaped mail, such as square or vertical envelopes, are charged a nonmachinable surcharge, even if they weigh less than 1 oz, as they require special handling and cannot be processed by machines.

If you’re sending a square envelope internationally, the cost will depend on the destination country, the weight and dimensions of the envelope, and the level of service selected.

For example, the cost to send a 1 oz square envelope from the US to Canada using USPS First-Class Mail International starts at $1.20, while the cost to send the same envelope to Australia starts at $1.70. However, the cost can increase significantly for heavier or larger envelopes or faster shipping options.

It’s essential to check with your local postal service or shipping carrier for the most up-to-date and accurate pricing information based on your specific needs and destination.

The envelope’s dimensions can affect its cost, as larger or thicker envelopes may require more postage. Additionally, the weight of the envelope and its contents will also play a role, as heavier envelopes will require more postage than lighter ones.

Here’s a table summarizing the postage requirements for various square envelopes based on weight and destination, along with the cost of each postage option. Note that the costs are accurate and may be subject to change.

Envelope SizeWeightDomestic PostageDomestic Postage CostInternational PostageInternational Postage Cost
4 x 41 oz.1 Forever Stamp$1.03Varies by destinationVaries
5 x 51 oz.1 Forever Stamp$1.03Varies by destinationVaries
5.5 x 5.51 oz.1 Forever Stamp$1.03Varies by destinationVaries
6 x 61 oz.1 Forever Stamp$1.03Varies by destinationVaries

For international postage, the cost varies based on the destination country and the weight of the envelope.

It’s important to note that if the envelope is thicker or heavier than standard mail, it may require additional postage. Therefore, measuring and weighing the envelope accurately is crucial to ensure it meets USPS size and thickness guidelines.

Do Square Envelopes Require Extra Postage?

If you’re planning to send a square envelope through the mail, it’s essential to know that it may require extra postage. Sending a square envelope weighing less than 1 oz or a rectangular envelope weighing between 1-2 oz (like most wedding invitations) within the US, you’ll need $0.87 worth of postage or one 2-ounce forever stamp.

This is because square envelopes are considered non-machinable by many postal services, including the USPS in the United States.

Non-machinable envelopes cannot be easily processed by mail-sorting machines due to their size, shape, or other characteristics. As a result, they may require additional postage beyond the standard rate to cover the extra handling required to deliver them.

The extra postage required for a square envelope can vary depending on its weight, size, and destination. It’s always a good idea to check with your local postal service to find the exact postage rate for your specific envelope.

Why Square Envelope Postage Costs Some Extra Cents?

According to USPS, Rectangular Envelopes are processed in a short period. Because an envelope can be grabbed by one of its longer sides, the machine can easily locate its upper and Lower end Corner.

It’s easy for a machine to read the address and route the person’s envelope easily.

On the other hand, square envelopes do not have a long side to land on the machine automatically. The machine will need extra steps to adjust and read the envelope easily. But it’s easy for a machine to remove a square envelope from the sorter. 

Human involvement is necessary to manually put the address into the system so that it may be routed to the correct post office

So that’s why there is a $0.87 surcharge due to the non-machinable envelope for the first Oz.

How Many Stamps Do you Need ?Does Publix sell stamps?

How Many Stamps for A Greeting Card?

After researching various sources, the number of stamps required for a greeting card depends on several factors, such as weight, size, and destination.

In the United States, the United States Postal Service (USPS) is responsible for delivering mail and packages, including greeting cards.

If a greeting card is 5 inches by 7 inches or smaller, the maximum weight is 1 ounce is being mailed within the United States, then only one Forever stamp is required, currently priced at $1.03. A Forever stamp can be used regardless of future price increases.

However, additional postage will be required if the greeting card is larger than the standard size or weighs more than 1 ounce.

For example: If a greeting card is 6 inches by 9 inches and weighs 2 ounces, it would require three Forever stamps, totaling $1.74 in postage.

It’s important to note that the postage cost will vary depending on the destination country if a greeting card is being sent internationally. The USPS provides an online calculator to estimate postage costs for international mail.

How Much Extra Postage for Papyrus Cards?

The extra postage required for Papyrus cards depends on size, weight, and destination. Additional postage will be required if a Papyrus card is larger than the standard size or weighs more than 1 ounce.

How Much Postage for a 6×6 Square Envelope?

To mail a 6×6 square envelope, you must determine the appropriate amount of postage based on the envelope’s weight and destination. For domestic mail weighing 1 ounce or less, a single Forever stamp, currently priced at $1.03, will suffice. However, for each additional ounce, an extra 87 cents is required.

For international mail, the postage cost will vary depending on the destination country.

The USPS provides an online calculator to estimate postage costs for international mail, which you can use to determine the correct amount of postage needed for your 6×6 square envelope.

It’s also essential to ensure that your envelope meets USPS size and thickness guidelines to avoid additional fees.

Postage For 5×5 Square Envelope:

The postage required for a 5×5 square envelope depends on the weight and destination of the envelope. If the envelope weighs 1 ounce or less and is being mailed within the United States, then only one Forever stamp is required, currently priced at $1.03.

However, additional postage will be required if the envelope is larger than 1 ounce or is being mailed internationally.

Using the United States Postal Service (USPS) website or visiting a local post office is recommended to determine the exact postage required for your specific 5×5 square envelope.

Postage For Square Envelopes 5.5 Inches:

The postage required for a square envelope measuring 5.5 inches will depend on its weight and destination. If the envelope weighs 1 ounce or less and is being sent within the United States, a single Forever stamp, currently priced at $1.03, is sufficient. However, for each additional ounce, an extra 87 cents are required.

For international mail, the postage cost will vary based on the destination country. You can use the USPS website or visit a local post office to determine the exact postage required for your square envelope.

Josh Wan

JoshWan is an industry veteran with over a decade of experience in Stamps & Postage, Open Close Hours, Restocking & Shipping, EBT and Pay, and General Topics. His expertise and dedication to these fields make him a valuable asset to our team. Trust his insights for all your niche-related queries.

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