How to Get the Right Size Mailer for eCommerce Shipping

Mailers come in all shapes and sizes, which can be confusing when trying to find the one that will work best for your needs. This blog post will walk you through how different size mailers are determined and what factors go into choosing the right mailer


Shipping is an important part of any eCommerce business. It’s crucial to get the right mailer in order to make sure that your products arrive at their destination in perfect condition. Mailers come in all shapes and sizes, which can be confusing when trying to find the one that will work best for your needs. This blog post will walk you through how different size mailers are determined and what factors go into choosing the right mailer for eCommerce shipping!

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What is the difference between a letter, flat, and parcel mailer

A letter mailer is typically the smallest size available. It includes a single piece of paper, an envelope with no plastic window or anything else enclosed. Letters are most appropriate for invitations, announcements and other correspondence that only require one sheet of paper folded into an envelope.

It does not include any protective packaging material used to mail the product, such as bubble wrap or peanuts; it only includes the mailer itself plus enough cushioning inside to mail the product, such as poly mailers. Letters are typically used for correspondence and invitations

Flats include several pieces of paper at least one side each, or any similar items that will not fit in a letter mailer (i.e., greeting cards). Flats also include any mailer or protective packaging material such as bubble wrap. Flats are most appropriate for small catalogs and other mailings that include letter-sized mailers.

Parcel mailers are generally made of paper or card stock, mailers can be made from a variety of materials such as corrugated cardboard, poly mailers or plastic mailers. Parcel mailers are generally used for shipping large items such as books, textiles, and clothing. Parcel mailers are often used when shipping products with an irregular shape or size to ensure they arrive in one piece. When shipping a small item, mailers may be used to protect the product during shipment and help prevent damage from dropping or breaking. When shipping a larger item, mailers help prevent damage by providing cushioning and shock absorption during shipment.

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How to determine what size mailer you need for your shipment.

When choosing a mailer size, it is important to consider the fit and padding. A mailer that fits too tightly may cause damage or destruction of your product if there isn’t enough protection. However, mailers that are too large can also result in shipping damages as they don’t protect items against shifting within the package during transit

Remember: Your mailer needs to be large enough for the mail and contents. This ensures protection during transit.

Do not forget: Make sure mailers are mail-ready! This means they have a closure that is compatible with USPS, UPS and FedEx. Remember to affix a shipping label with the correct postage.

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Tips on how to pack items in a mailer so they arrive safely

It is important not to over-stuff a mailer, as this can cause it to be misshapen when sealed and also prevent proper delivery. Adding just enough filling material inside will allow the mailer wrapper to fold cleanly around the mailer. For mail-pieces that are too small, use dunnage to fill out the mailer so it is properly shaped and will not crush under its own weight

If your product has sharp corners or edges, consider adding soft dunnage around these corners or edges to prevent damage before shipping. Sharp corners can rip mailers and damage mail-pieces inside. This is because the mailer wrapper or envelope has to stretch when it closes, so adding extra filler material to the mailer will help reduce damage.

The biggest problem most people have with mail-pieces getting lost or damaged in shipping is from a poor quality of seal. Either an envelope mailer is not sealed at all or the seal was not made securely. To ensure your mail-piece gets where it needs to go, make sure you use mailers that have a strong adhesive and that your mailer has not gaps in the seal where an item can fall out.

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When it’s time for new packaging supplies

While you might not think about it very much, choosing the right mailer is a critical step in shipping your products. Sometimes you will need to by a new or different mailer to accomplish the task at hand.

Even if you have been using mailers from the same company for a few years, it is important to make sure that you are getting mailers that fit your products. This will save you time and money, because it is much easier to package an item in the right mailer.

There is definitely such thing as an envelope that’s too big or small for its contents and you’ll want to avoid using mailers with these problems if at all possible. In a mailer that is too big items can move around and get broken or damaged. In mailers that are too small, on the other hand, leave your products vulnerable to shipping hazards due to the mailer’s lack of cushioning.

Most mailers are made with different weight papers and plastics. It is important to use a mailer that can support the weight of your product. If it’s too light, mailers may rip or tear during shipping and items can be lost or broken in transit.

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The best ways to save money with eCommerce shipping 

The best way to save money on shipping supplies is to mail things in a mailer. These mailers are usually cheaper than boxes and can be reused for shipping. There is a lot that goes into mailer sizing, but for the sake of this article we will mention the three most common sizes sold online; #0 (small), #00 (medium) and #000 (large).

The best way to measure your mailer is with an envelope. Fold it in half so that you have a crease line indicating where the mailer should be measured from. This will give you an idea of what mailer size to get based on the dimensions of your product. Of course, a mailer that is too big or small for a good fit could cause issues with shipping and may increase costs in some cases.

The best way to save money with eCommerce shipping is by getting sizing down correctly before you order your supplies, but sometimes the mailers don’t fit right or aren’t big enough for what we need. So how do mailers effect pricing? The general rule is that mailers get more expensive the bigger they are. So a small mailer will cost less than a large mailer and so on.

The general rule of thumb with mailers is to get one bigger than you think you need, but not so big it leaves room for shifting in transit. It is better to mail something in a mailer that’s slightly too big than one that’s way too small.

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Why it’s important to have the right sized mailers when shipping smaller packages- even if you’re not an eCommerce seller!

Using the right mailer size is important even if you don’t own an eCommerce company. Mailers can be reused for different types of shipments and postal services may charge additional fees based on how you package an item, mailers are a cheap and effective way to mail most items.

Mailers can also be reused to wrap gifts and presents. This is a cheap and ecofriendly way to package a gift by reusing materials from your online shopping orders.

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Shipping is a crucial part of any eCommerce business. Ordering the wrong mailer can result in your products arriving at their destination with damage, which will cost you time and money to replace them. That’s why it’s important for all parts of an order fulfillment process to be as seamless as possible! If you need help shipping or storing your products, we have experts ready and waiting to provide assistance. What sort of items do you like to ship in mailers?

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