Direct Mail

USPS Regulations

By 11 May 2022No Comments
usps marketing mail standards

How To Ensure Fast Delivery Of Your Mailers By Complying With Usps Mail Standards?

Is your organization’s direct mail delivery rate or delivery time going down despite using verified postal addresses? If yes, then the reason behind your troubles could be the USPS mail standards. The mail standards ensure that USPS’s sorting/processing equipment can quickly process your direct mail.

usps marketing mail standards

Unfortunately, many businesses are still unaware these business standards even exist. Hence, we have taken the liberty to explain precisely what USPS regulations are and why they are so vital for businesses. In addition to that, we also present the USPS mailing requirements for different types of mailers and how you can meet those requirements.

What are USPS Mail Standards, and Why Is It Important?

As you know, USPS offers the most extensive postal mail service within the US. It has a post office in almost every nook and corner of the country. USPS puts forth a set of rules and regulations to ensure that your postal mailers are processed and delivered on time.

As much as you may hate rules and restrictions, it would be best if you still meet these USPS restrictions. Why? Because these rules and regulations from USPS ensure that your mailer reaches its destination on time without getting destroyed.

It might be okay to take the risk of not meeting these regulations when you are sending a Christmas card to your parents. But, if you are a marketer or business owner sending bulk mail and choose to ignore these regulations, you are practically flushing money down the drain.

Because if you don’t meet the USPS mail standards, there is a good chance that your business mailers will not get delivered. If you look at the complex sorting process and the heavy equipment USPS use for sorting your mailers, you will understand why.  

USPS Self-Mailer Postal Regulations

Self-Mailers are perhaps the most common postal mail businesses use for direct mail marketing campaigns. However, many of these businesses still don’t know the USPS restrictions surrounding self-mailers and their tabbing.

And in the end, they are left wondering why their mailers never got delivered despite ensuring the validity of addresses. To help you avoid such situations, we have listed all the USPS regulations for a self-mailer.

Basic USPS Mailing Requirements For Self-Mailer 

The primary mailing requirements of a self-mailer refer to its dimensional conditions. As you know, a self-mailer typically has two or more panels. For self-mailers, we fold together one or more unbound sheets of paper to form a letter-sized mailer.

According to the USPS mailing requirements, you have a standard range of dimensions for all your self-mailers. The standard sizes for your self-mailers are mentioned in the table below.

Dimension Minimum  Maximum
Height 3.5 inches 6 inches
Length 5 inches 10.5 inches
Thickness .007 inch .25 inch
Weight _ 3 ounces

Note: It is worth noting that it is okay for your business to use a self-mailer with 0.009 thickness as long as the height is over 4-1/4 inches. Similarly, the same dimensional limit applies if the mailer’s length is more than 6 inches.

USPS Restrictions On Self-Mailer Panels

Self-mailer postal regulations also apply to the number of panels. Panels are the sections formed when you fold up a self-mailer. Each two-sided section of the self-mailer separated by folds is considered a panel.

As you can guess, the total number of panels includes each such panel. But don’t forget to count the front and back panels. Now let’s move on to the maximum number of panels allowed by the USPS regulation.

As per USPS restrictions, your self-mailer can have 12 panels at max. However, this number is not set in stone as there are some exceptions. In addition to that, you must ensure the last folded edge is positioned at the bottom unless you are using an oblong piece.

USPS Restrictions on Self-Mailer Flaps

You might have noticed that some self-mailers have flaps. To get these flaps, you fold over the last panel of your self-mailer, and it is attached to the unaddressed side of the mailpiece. It might surprise you that the USPS has some regulations for these self-mailer flaps.

  • According to self-mailer postal regulations, the flap must measure 1 to ½ inches from the top of the mailpiece
  • The folded edge of the self-mailer should align with the top of the mailpiece
  • The flap should not extend beyond 1 inch over the bottom edge (However, there are certain exceptions.)
  • If your marketing mailers are die-cut, USPS requires them to be secured with tabs or glue lines/spots

USPS Tabbing Requirements For Folded Self-Mailers

You may be already aware of the significance of tabbing for folded mailers. Nonetheless, you need proper tabbing to prevent the open edge of your mailers from jamming USPS’s high-speed processing equipment.

Furthermore, the USPS restrictions may vary slightly for different types of folded self-mailer. But, the good news is that we will discuss all of these restrictions with you specifically for each type of mailer. So let’s get straight to it.

USPS Tabbing Requirements For Bi and Tri-Fold Self-Mailers

Let’s start with the basics. A bi-fold self-mailer is one that you fold once and has two panels. On the other hand, a tri-fold self-mailer is folded twice and makes up 3 panels.

The USPS tabbing requirements for bi and tri-fold self-mailers are pretty much the same, which is why we have clubbed them together here.

The tabbing requirements for your basic self-mailers with two or three folds are as follows.

  • Use two tabs of one-inch diameter for a mailpiece that weighs up to one ounce
  • Use two tabs of at least one inch and a maximum of one and a half inches in diameter for a mailpiece that weighs over one ounce
  • According to USPS tabbing requirements, you can place the tabs in two places on the mailer
  • Place one tab each on the center top edge and center trailing edge
  • Place both tabs on the railing edge within 1 inch from the top and bottom edges, respectively

USPS Tabbing Requirements For Oblong Folded Self-Mailers

An oblong folded self-mailer forms 2 rectangular panels when you fold it. The panels have one elongated area, and they are not so different in shape from bi or tri-fold self-mailers. Here are the USPS tabbing requirements you need to follow for oblong folded self-mailers.

  • An oblong self-mailer that weighs up to one ounce requires two tabs of 1-inch diameter
  • An oblong self-mailer that weighs over one ounce requires two tabs of one to one and a half inch diameter
  • The final folded edge of the oblong self-mailer must lead to the right edge

USPS Tabbing Requirements For Quarter Fold Self-Mailers

The quarter fold self-mailers are created by folding the paper twice, with each fold at a right angle to the previous fold. In other words, quarter fold self-mailers create four panels when you fold a sheet of paper four times. The USPS tabbing requirements for quarter fold self-mailers are as follows.

  • Use two tabs of one-inch diameter for quarter-fold self-mailers that weigh up to one ounce
  • Use three tabs of at least one inch and a maximum of one and a half inches diameter for a mailpiece that weighs over one ounce
  • If you are using newsprint, you must use three tabs of at least one inch and a maximum of one and a half inches in diameter
create direct mail letter

USPS Mail Standards For Booklet-Type Mailers

The booklet-type mailers are another type of postal mailpiece that your business can use for marketing purposes. Usually, the booklet mailers are unfolded printed materials. Hence, the requirements for USPS when it comes to booklet-type mailers are different from the folded mailers.

Although booklet mailers are usually product catalogs, you can insert brochures, pamphlets, and unfolded unbound paper stacks. Many companies use booklet-type mailers for marketing their business. If you are one of them, you should take your time to learn about the USPS restrictions surrounding them.

Basic USPS Mailing Requirements For Booklet-Type Mailers

Much like every other type of mailer, the booklet-type mailer also comes in various sizes. However, the most commonly seen booklet mailers are 8.5 x 11 inches in size. However, you can create smaller-sized booklet mailers that easily fit into 6×9 inch envelopes. 

Letter-Sized Booklet Mailers

Dimension Minimum  Maximum
Height 3.5 inches 6 inches
Length 5 inches 10.5 inches

Larger Booklet Mailers

Dimension Minimum  Maximum
Height 6 inches 12 inches
Length 10.5  inches 12 inches

USPS Tabbing Requirements For Letter-Size Booklet-Type Mailpiece

The booklet-type mailers also have specific regulations like the postal tabbing requirements we discussed for folded self-mailers. Having these regulations is also the same – to ensure speedy processing and non-stop processing of mailers.

When sending a booklet-type mailpiece for your business, ensure that the spine or bound edge is at the bottom. In addition to that, the spine must be parallel to the booklet’s longest dimension and the mailpiece’s address.

Now, as far as the postal tabbing requirement for booklet mailers goes, there are two ways you can place your tabs.

Case 1

  • Use at least two tabs or wafer seals on the top or unbound edge
  • The tabs or wafer seals must be placed within one inch of the left and right edges of the booklet

Case 2

  • Secure the left (trailing) and right (leading) edges with tabs or wafer seals
  • Make sure to place the tabs or wafer seals within one inch of the booklet mailer’s top left and top right edges

Apart from the two ways of placing tabs listed above, you also need to know the following USPS tabbing requirements for booklet mailers.

  • For booklet mailers that do not exceed 4.5 inches in height and 6 inches in length, you can use a 1 tab or wafer seal. The position of the tab or wafer seal must be in the center of the trailing left edge
  • For booklet mailers that exceed 4.5 inches in height and 6 inches in length, you need to use 2 tabs or wafer seals. In this case, the tabs or wafer seals must be placed within one inch of the bottom and top edges of the booklet mailer

USPS Tabbing Requirements For Flat-Size Booklet-Type Mailpiece

As you may know, flat size refers to the dimension of the mailer or document after it has received any necessary trimming and printing. But this dimension is the one you have before you subject the mailer to any operations like folding that can change the mailer’s size.

As for the USPS booklet mailing requirements for flat-size booklet-type mailpieces, here are the things you need to know.

  • Sleeves And Wrappers: When using sleeves and wrappers for your flat-size booklets, ensure the contents are securely in place. In other words, ensure that the sleeve or wrapper stays in place during the processing of the mailer
  • Partial Wrappers: When using partial wrappers, ensure the delivery information or barcode for the mailpiece is tightly secured. Make it a point to ensure that contents don’t shift around and obscure the barcode or delivery address

USPS Mail Standards For Postcards

Postcards are the most commonly used direct mail marketing mailer for businesses. Hence, it would be best if you learned about any USPS restrictions surrounding the marketing postcards you send. Postcards are the preferred medium for direct mail marketing for most companies because they are the most cost-effective.

Furthermore, they are easy to design, and there are a lot of templates available online too. We at PostGrid offer a free template gallery where you can find attractive postcard templates for your campaigns.

Basic USPS Mailing Requirements For Postcards

Dimension Minimum  Maximum
Height 3.5 inches 4.5 inches
Length 5 inches 6 inches
Thickness .007 inch 0.061 inch

You can get a more comprehensive view of the different postcard sizes you can use for your business on our ultimate guide for postcard sizes.

USPS Tabbing Requirements For Postcards

Compared to the other postal mailers, the USPS tabbing requirements for postcards are pretty simple and easy to follow. Below are the tabbing requirements you need to follow when sending postcard mailers.

  • Secure the open edge of the postcard with a single tab positioned in the middle
  • If you are using double postcards, make sure to have a folded edge either at the top or bottom

How PostGrid Can Help You With USPS Mailing Standards

As you can see, there are a lot of USPS mailing requirements for sending a marketing mailer for your business. It is hard enough to design and print marketing mailers for businesses. Keeping track of the mailing requirements makes it even more difficult than it has to be. 

Of course, you can save yourself all this trouble with the help of PostGrid – a fully automated direct mail solution. PostGrid takes care of all aspects of your postal mail process, including personalization, printing, and delivery of your mailers.

More importantly, PostGrid ensures all the USPS mail standards for your marketing mailers. Furthermore, it does not matter what kind of mailer you want to print, whether it is a postcard, a booklet, a brochure, or anything else. PostGrid can meet all your direct mail needs.

Ensure Maximum Deliverability Rate

As PostGrid ensures that all the USPS mail standards are met, there is simply no reason for your mailers to go undelivered or even get delayed. The direct mail automation tool even prints the addresses per the USPS’s standard format.

Securely Send Sensitive Direct Mail 

PostGrid is a favorite among industries, including healthcare, insurance, and finance, because of its highly secure printing tech. 

It even has HIPAA compliance which guarantees the safety of patient data. Hence, it is the best direct mail solution for sending documents like patient billing statements.

For example, you can learn how you can improve healthcare communication using direct mail by clicking here.

Industry-Specific Direct Mail Services

PostGrid offers specialized printing services for a variety of industries. It includes industry verticals with complex printing needs like healthcare and financial services. We help our clients regardless of how demanding their direct mail needs are while not compromising on USPS mail standards.

As part of the project, we enable our clients to send plan insights, thank you postcards, and more in bulk. We ensure regular direct mail communication with advanced direct mail scheduling capability. In addition to that, we successfully scale up the delivery of direct mailers for our clients.


The number of USPS restrictions for mailers is practically endless, and most of us are unaware of these regulations. It becomes increasingly difficult to keep track of these regulations when it comes to bulk mail. However, ignoring these restrictions could mean that your mailer may not get delivered.

The most convenient way for businesses to keep up with USPS mailing requirements is to employ an automated solution. Direct mail solutions like PostGrid can ensure all your mailing needs while ensuring all mailing standards for your mailers.

Using advanced solutions like PostGrid, you can ensure proper tabbing for your bulk mail. You can even print addresses as per the format described by the USPS. As a result, your direct mail is always delivered on time, and the deliverability of direct mail improves significantly.

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