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The Ultimate Guide To Mailer Boxes

The Ultimate Guide To Mailer Boxes

By: Hadyn Oliver

7 Minute Read

What’s a great way to ship your products in a professional but stylish way?

It has to be the mailer box! 

You may wonder, what’s wrong with the standard 4 flap (0201) style shipping box? Or you may be asking why is the mailer box used so widely among brands?

Well, here’s your answer …

Not only are they durable and hard wearing, they are fully customisable. It provides a great way to promote your brand and create the ultimate unboxing experience for your customers. 

But hang on, before we get going to far into this – you need to know that postal boxes, mailing boxes, ecommerce boxes, subscription box are all the same thing, just different people call them different things. 

Right, now we have that cleared, let’s have a look in a bit more detail:

Mailer Boxes: Shipping Essentials For E-Commerce 

If you’re in the retail sector, mailing boxes can be used for anything from gift packaging to sending out promotional materials. Because they are easy to assemble, efficient, and effective, they are the perfect0427 mailer box way to keep your orders safe and secure while in transit. 

Mailer boxes have been around for a long time, but a lot of brands are yet to grasp their awesomeness. With the online orders increasing at a fast rate of knots, the unboxing experience has become the next most important thing for customers. 

A lot of retailers offer a subscription service. This is where a customer signs up to receiving a product once or twice a month on a repeating order. The product arrives in a customised mailer box which is very versatile as they can fit all sorts of size items. Anything from razors and makeup, to video games and dog biscuits can fit into the subscription box. The items can be placed attractively into the box to give the customer an excellent experience.

But that’s not all, they’re not only used for subscription services. Business use them to send out items like books, catalogues, merchandise, and anything that you can order online. 

That’s means there is large amount of mailer boxes being sent around the world every day!


Now, let’s take a look into how you can get the most from your mailing boxes …

Building your brand with the mailer box

A few years ago, companies put all their focus into the product and paid little attention to the packaging. They gave little thought into what kind of box the customer received, and didn’t even really know about the whole “unboxing experience”. 

About Us Image - SustabioBut times have changed, things move on …

If you ignore your packaging these days, you’re likely to be missing out on a highly effective marketing strategy and probably losing customer because of it. 

When a customer buys an item, they don’t just want the item, they are the buying the whole experience. From the product image online, to the smooth checkout and order confirmation, all the way through to the receiving the product and taking it out its packaging. It’s all part of the experience. 

But you may say, why a mailer box?

It’s customisation that tops it. Even if you’re a small startup, giving a customer a good solid piece of packaging, is going to boost their mood. Even if you’re a tiny little Etsy seller, or a well established brick-and-mortar store, you can use a mailer box effectively, efficiently, and successfully. 

When designing a mailer, they offer a lot of flexibility, you can:

  • Add your own unique design to tell your story
  • Use logos to promote your brand name and gain awareness

But … there is a key point to remember when branding a box, not just a mailer box, any box …


You must, must, must think about the colours you are using, do they match your website? Your business card? Your marketing brochures? Everything that shows your brand name and logo should be the same colouring and font. 

It helps consumers to notice it and say “Oh yes, that’s XYZ”

Social Media and Unboxing Videos

We’ve mentioned this in previous posts, but it’s so important…

I bet you’ve opened some form of social media today, whether it be Facebook, Twitter, LinkedIn or Whatsapp, but nearly everyone uses it – In fact 4.76 billion people use it!


Now, just imagine this. If one of your customers posted a video of themselves receiving, opening, and unpacking their product on social media. Think of how many people would see it and read your brand name, notice your brand colours, and hopefully remember them!

You may think, hang on, people don’t really watch these unboxing videos, they just flick by them. But you’re wrong, the amount of people who would go onto YouTube to find an unboxing video of a product before purchasing is surprisingly high. These types of videos are strongly addictive and have become very popular over the last 3 years. 

If you google Unbox Therapy, they are a channel with over 18.2 million subscribers and his videos reach over 4 billion views. Crazy right? It’s a crazy amount of views for an unboxing video, and also a crazy amount of brand awareness if your packaging is right. 

Moral of the story is, if you want to get noticed by customers, your overall presentation is key – and that includes your packaging. A cleverly designed mailer is going to give your products a far higher perceived value. 


OK, so by now you should have a better understanding of the importance of a good-looking mailer box. 

Now, let’s take a look into the features of a mailer box and which you should go for. After all you want your box to be high quality and attractive. 

Features of a mailer box to look out for

Don’t you hate it when you receive a quote with a load of numbers and letters you don’t understand. 

150K/150T BC FSC Mix 70% Glued 0201

What on earth does it mean??

1. The Paper Grade

Durability is a must for mailer boxes, that’s why they are more often than not made from some type of corrugated material. 

  • KRAFT CORRUGATED CARDBOARD – This is your standard brown mailer. One you’ve no doubt used or seen before, but it’s a very affordable, rustic mailer with a natural look. They’re usually a good eco option as they’re made from recycled materials. 
  • UNCOATED WHITE CORRUGATED BOARD – Some people prefer a white board, as it looks clean, and graphics stand out more. If you’re a high end brand, this would be a good choice.
  • CLAY-COATED CORRUGATED BOARD – OK, not so popular but it has a smooth, bright surface. It tends to be very costly and would only be used by top luxury brands. 

These are the 3 main boards you’ll see when asking your supplier for a mailer box, but there’s also a load of different thicknesses to consider. We’ve put this table together to help you understand it …

Flute TypeThickness (mm)MicronsFeaturesUses
E Flute1.1mm – 1.2mm1100-1200 micronsCrush resistant. Good compression strength. High quality printing surface. Smaller mailer boxes. Bespoke size mailers.
S Flute2.3mm2300 micronsOutstanding printability. Strong crush resistance. Retail and transit packaging
B Flute2.7mm-2.9mm2700-2900micronsMost common flute. Good all-round performance.Bespoke size mailers. Transit packaging.

There is many other flutes available out there, but we picked out the most common to help make things a little simpler for you.

The thickness of your mailer depends on how fragile your products are, the more fragile, the thicker the board, obviously. 

No matter the thickness of material, any type of box can be well designed with even a small budget. A simple brown box with a logo printed on the lid can create more of a memorable impression than you think. 

Even if your budget is almost non-existent, there’s ways and means to customise your mailer. Get a custom hand stamp with your logo, or even a sticker which you can put on your box, something that will make your box more than just a box. 

2. Closures

Your box needs to be quick and easy to assemble to allow for an efficient packing process. Regular shipping boxes tend to require some form of tape or glue to seal, whereas a mailer can have a self-adhesive strip, making it far easier to seal. eCommerce Mailer Box

You can even go one step further with a perforation strip to allow customers easy access into the box, plus, a return strip so customers can send back any unwanted items. 

3, Printing

As mentioned, printing is a big feature of your box. No print, no memorable first impression. 

Text and graphics need to be looking crisp and of high quality. A blurry image is just going to put people off. 

Your current supplier may have already mentioned the printing process but, there is 2 main colour processes used. PMS (Pantone Matching System) which is the cheaper option if you’re printing 3 colours or less. CMYK (Cyan, Magenta, Yellow, Black) which is great for printing a full colour photo. This options great when printing a variety of different colours. 

There are also 4 different ways to print onto your mailer:

  • FLEXOGRAPHY (Flexo) – This is a popular option due to its speed and affordability to print onto both rough and smooth materials. 
  • DIGITAL PRINT – Gaining popularity due to its high quality and speed of print, it tends to be best for smaller volumes. 
  • OFFSET LITHOGRAPHY (Litho) – Great for printing labels and high quality photos. Tends to be slightly more expensive than Flexo and Digital. 
  • FOIL STAMPING (Hot stamping) – This gives an elegant, sophisticated look by pressing foil onto the surface of a box in the shape of a logo. A black box with a gold foil logo is a very popular choice. 

Whenever your designing your artwork for a mailer box, remember that you want quality – your images need to be perfect so they print with the highest of quality. 

4. Finishes

OK, a printed mailer is very attractive. But you could take it next level by adding a coating or extra finishing touches. It gives your box a high end, polished look. These aren’t a necessity but kind of a nice option if you’ve got a bit of extra cash on your budget. 

Phew, that’s a lot of information just piled on you. Let’s take a breather and quickly recap what we’ve learnt:

What To Look ForFeature/QualityMailer Box Description
Paper GradesKraft Corrugated CardboardBasic brown box with a rustic, natural look.
Uncoated White Corrugated CardboardWhite mailer that gives a clean, high end look.
Clay-Coated Corrugated CardboardSmooth, bright surface but higher price.
ClosuresSelf-Adhesive StripsMakes it quicker and easier to seal the box.
Tear StripsAllows customers to open the box with ease.
Return StripsCreates an efficient, sustainable way for customers to return items.
PrintingFlexography or FlexoGreat for printing a range of materials. Affordable and fast way to print
Digital PrintHigh quality but best for smaller quantities
Offset Lithography or LithoPerfect for labels or high quality photo prints.
Foil Stamping or Hot StampingUses foil to give an elegant, luxury look to your printed logos.

Time to move on ….

Keep your custom mailer boxes eco-friendly

E-commerce is booming. 

Custom Packaging - Slider - Sustabio Home PageAnd that means an increased amount of packaging waste in landfill and oceans. This is more than a huge thing for customers and businesses alike. You can’t go a day without seeing some news about climate change or environmental disaster. OK, consumers love to but the latest and greatest, but at the same time they’re concerned about the environmental impact of their purchase. 


We know there’s no way we can totally stop the environmental impact of packaging yet, but customers appreciate it if you do your bit as a brand.

Use a mailer box. Not only are they quick and easy, but they are one of the most eco-friendly options for packaging out there. 


  • Made from post-consumer recycled materials
  • Continually recyclable – 96.5% of corrugated board is recycled
  • Easy to ship. Lightweight and stackable so save space in transit. 
  • Biodegrade far faster than plastic. 
  • Sustainably sourced – a lot of manufacturers have FSC or SFI certification to prove this. 
  • Sturdy enough to be reused over and over again. 

Now, some of you out there think “oh, eco-friendly is so boring”. But it’s not, you can still have a fully water-based, soy-based, or even algae-based ink for an eco-print. So don’t let environmental concerns limit your design. 

The inside

Even though postal boxes are durable and strong, it doesn’t mean you can simply put an item inside, seal it up, and throw it around without the product getting damaged. So it’s quite important to either makeCustom Packaging Image - Sustabio Home Page the mailer to suit the size of the item, or use some extra protection on the inside. 

  • PACKING PAPER – Eco option to fill space and provide protection. You can wrap items individually or roll it into balls to cushion your goods. It looks decent and is recyclable. 
  • TISSUE PAPER – affordable yet simple way to elevate your packaging. Doesn’t necessarily provide protection but helps get rid of empty space. 
  • CARDBOARD INSERTS – This is great for protection. They are made to fit a particular item and provide a cushion around it to stop it from breakages. 
  • FOAM CUSHIONS – If you’re items are super fragile, these will help provide that extra bit of protection.
  • AIR PILLOWS – Not very aesthetically pleasing, but lightweight, easy to store and do what they’re meant to do. 

You may also throw a few goodies in to fill the empty space, maybe a sweet, brand notepad or pen, or even just a brochure – your customers will love it. 

A little inspiration

Having loads of options is a good thing, but so overwhelming at times. So by looking at what others have done, you can brainstorm some things to avoid and things to include. 

Let’s take a look at some peoples mailers:

1. Lily and Onyx

Lily and Onyx Mailer BoxLily and Onyx curate locally and internationally crafted goods that promote mindfulness. They use the mailer to ship items to customers and have designed it with a simple, yet tasteful design. They’ve used a white uncoated board with some paper shredded voidfill to add that extra protection. The simple inside print “Enjoy the little things” gives that extra something to a customer when they open the box. 

2. Love With Food

Love With Food Mailer BoxLove With Food provides a snack delivery service. They pack their snacks into the mailer boxes then send them to customers when ordered. The simple yet attractive design is great. A bright red colour is going to stand out from its competition and with the simple logo and small amount of text, it’s easy to read and remember.

3. greenUP Box

greenUP provide a subscription service dedicated to reducing waste and plastics in everyday essentials. Not only are their products eco, but so is their packaging. The leaf covered, green mailer box represents their brand colours and gives you the sense that what they provide is eco. The simple, minimalistic design looks smart yet good-looking and attractive. 

Use a mailer box to spotlight your brand

If you’re at the stage where you have your great product – don’t leave your packaging till the last minute. It’s a critical part of your marketing plan to gain brand awareness and improve customer satisfaction. 

Not only does designing it take some time, your supplier has to then cut to size and print which tends to have a fairly long lead time. 

So to end this post off – my top tip is a well designed mailer box can up your game, boost your brand and in turn, boost sales. So put the hard work into designing, make it memorable and attractive and you’ll see the results .


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