Evaluating Which Direct Mail Format is Right for…Your Customers

Did you know that direct mail and the postal system we know today originated on July 26th, 1775, led by none other than founding father Benjamin Franklin?  At the onset, the postal system allowed people to communicate with one another far and wide.  It’s surprising looking back, but it took business nearly 100 years to leverage this channel for what we now call direct mail marketing.

While it’s evolved over the years, one thing remains the same.  Direct mail is an efficient method to physically place your message and offer into the actual palm of your target’s hand.  Something increasingly rare, and something increasingly powerful, in today’s digital world.

Naturally, if you ask any marketer if they’d be thrilled knowing that their message and offer were physically held and looked at, even if momentarily, most would be smiling.  Ask their bosses what they think, and you’ll likely get pointed questions about response rates and ROAS.

Let’s Talk Direct Mail Myths

Direct Mail

Direct Mail

Direct mail is an “expensive” channel…60% of surveyed marketers said direct mail has the biggest ROI via CompereMedia (Check out our ROI calculator.) Direct mail is a “dying” channel…average response rates increased from 2.9% to 4.9% via Data & Marketing Association. Direct mail is an “older” channel…62% of Millenials reported visiting a retail location in the past month because of direct mail via USPSYou can review our own client direct mail marketing case studies here

Direct Mail Formats

After being in direct marketing, much of it direct mail, for nearly 20 years I’ve seen a lot of different mail kits.  To help you more easily evaluate which direct mail format is right for you we’re focusing on the more popular mail kits.  From there we’ve developed a S.P.I.C.E. Rating System that evaluates each mail kit by the following criteria:

SpeedHow quickly can the piece be produced and how quickly can it be delivered?
PrivacyAbility to include sensitive information on the direct mail piece.
InformativeHow much real estate you have with the mail kit for additional information.
CostWhat kind of budget implication does the mail kit have?
EngagementRating the engagement level of each piece?
S.P.I.C.E. Rating System

While it’s important to consider many aspects of your mail piece from design, messaging, offers, budget, and call-to-actions, today we’re just going to focus on the mail format itself solely. Of those, we’re going to be focusing on the most common formats, and the ideal scenarios where these will be used.

Letter Mailer

Letter mailers are your classic mail kit that has the actual letter encased within an envelope.  While there can be varying page and envelope sizes the most common combination would be an 8.5” x 11” letter folded to fit within a #10 envelope that measures 9.5” x 4.125”.

When done well, letter mailers can be great and driving engagement, with ample real estate for messaging and calls-to-action. They afford you the best privacy of all mail kits featured and can include additional components inside such as buck-slips and remit envelopes which make them ideal for non-profit appeal campaigns.

Speed (3)

As you’ll see for most of the mail pieces, letter mailers get a score of 3.  Let’s be honest and admit that when it comes to the USPS you’re getting the tortoise and not the hare, but like the childhood fable, they still finish with good results.

For the most part, when it comes to direct mail formats you generally have two primary delivery options:

    1. 1st-Class or Bulk Mail  1st-class is more expensive it does generally get delivered in 3-5 days vs. marketing mail which may take 4-14 days.


  1. Standard Mail (recently re-branded as Marketing Mail). – Marketing mail could even take longer if USPS is experiencing abnormally high volumes, which commonly happens around political primaries or mid-terms, and of course the holiday season.

Privacy (5)

Letter mailers are the most private form of mailings which makes them ideal for any industry that deals with sensitive information like healthcare or finance.  Privacy can be enhanced even more with alternative outer envelopes that can be coated/lined with black-out material that make it impossible to see what’s inside.

Informative (4)

Because letter mailers are typically at least 8.5” x 11”, and can include additional inserts, there is ample room to include a lot of information.  It’s widely accepted that story-telling is the best way to get people to remember your messaging, and a letter mailer gives you the real estate to be able to develop a compelling story.  Having the option of inserts allows you to create visually appealing pieces like an infographic/product profile/coupon.

Cost (4)

Even though letter mailers have a higher cost score here, they’re still considered an economical mailing option.  We’ve seen heavy fluctuations this year with paper supply chain issues, but like any other marketing campaign, upfront planning can get ahead of that.  It’s also worth considering that letter mailer costs are largely variable depending on the size of mailer, presence of inserts/remit envelopes, and of course postage rates selected.

Engagement (5)

Because of the highly flexible configurations with letter mailers, you can create a highly engaging direct mail piece.  Right off the bat letter mailers create a sense of intrigue because the messaging/offer is buried within the outer envelope.  Add this to the fact that you can include visuals and compelling messaging to tease the recipient to open up.

Now consider all of the different configurations from the actual size of the envelope, the ability to include inserts and/or remit envelopes, and the ability to include additional pages within…you’ve got a highly versatile and intriguing mail kit to the end recipient.


Self-mailers are essentially lettered mailers that are folded and sealed, either with tabs or glue dots that essentially turn the letter itself into a pseudo envelope.  This allows you to have visually appealing graphics/messaging on the outside of the folds, with a full sheet of info once opened up.

These are great because they’re a lower-cost option that still allows for ample room for additional information.  Self-mailers work great for service-based businesses that want to include different features/options.  They’re also great for retail-based businesses, especially within the food industry.  We do copious amounts of menu self-mailers that we saturate around our client’s locations to increase visits.

Speed (3)

Just like letter mailers, self-mailers have the same primary mailing options of first-class or marketing mail.  Unlike letter mailers, self-mailers are slightly faster because the actual production process is quicker.  You don’t have to worry about inserting, and you don’t have to worry about matching letters to envelopes.  This allows the self-mailer to be printed, addressed and delivered to the USPS more quickly.  Delivery times at that point depend on the mailing class you’ve selected.

Privacy (4)

Because self-mailers are folded and “sealed” you do have the ability to conceal information within.  However, because the mail piece isn’t sealed across all edges it would be possible to see within which wouldn’t make it ideal for the healthcare and financial services campaigns mentioned in the letter mailer section.

Informative (4)

Self-mailers can come in different sizes, but the standard 8.5” x 11” allows for ample room for your messaging and offers.  The outside edges make great spaces for calls-to-action, location/directions, and contact info, while still having room within for more detailed breakouts.

Cost (3)

Given the self-mailer is a fully self-contained mail kit you don’t have the extra cost of envelopes or inserts to worry about which lowers the cost.  That’s not to say you couldn’t have a larger format self-mailer which could influence the cost, but overall this is a more budget-friendly mailing option when compared to the letter mailers and booklet/catalogs.

Engagement (3)

Self-mailers lend themselves to being more promotional in nature, which may reduce some interest.  However, if the graphics and messaging on the outside are done well, they’ll encourage the recipient to want more.  The easy-open nature of the self-mailer will also help prompt recipients to open up from a tactile standpoint.


Postcard examples for direct mail marketing

Postcard examples for direct mail marketing

Postcards are the billboard equivalent of direct mail formats.  I love this metaphor because with postcards you have what’s called the “impact side”, which is the non-address side of the mailer.  The impact side should be used to peak the interest of the recipient.  The best way to do this is to have a visually strong image coupled with a short and concise message prompting the reader to flip over and learn more.  *Note: Less is more when it comes to the impact side so be especially diligent here.

Speed (5)

I’m not sure if there is such a thing as a fast tortoise, but if there is postcards would fit the bill.  Because the messaging piece is also the actual delivery vehicle the production process is incredibly efficient.  In fact, the design/message and address/postage can all be printed simultaneously at times which helps get it to USPS sooner.

Privacy (1)

A postcard by its very nature doesn’t allow for any privacy so this isn’t a good option if that’s a requirement of yours.

Informative (2)

Postcards get a lower score because they simply don’t have as much physical real estate to allow for larger amounts of information.  That said, postcards are really meant to be a vehicle to peak interest and then drive to a location, landing page, or other outreach.

Cost (1)

From a production standpoint of materials, and processing, postcards are the easiest direct mail format to produce.  Postcards also have more affordable options with USPS, including a recent change where they allow larger postcards to qualify for marketing mail rates.

Engagement (2)

Postcards get a lower engagement score because of format and real estate.  Postcards don’t have the ability to build intrigue in the way that envelopes, or even self-mailers since all information is exposed upon delivery.  The postcard format is also just smaller in nature which reduces the amount of room to build.

Direct Mail Marketing Statistics

Direct Mail Marketing Statistics

When it comes to postcards I like to think of the acronym K.I.S.S., which stands for Keep It Simple Solicitor.  Postcards are great for an industry like real estate, where you want to drive the recipient to a landing page or to prompt a call.  They’re also great for retail where you can feature products and coupons that push for in-store visits.


Every Door Direct Mail (EDDM)

This really should be labeled “Postcards Part Deux”.  Several years back the USPS created a heavily discounted postal rate in an effort to encourage businesses to use direct mail more.  However, because we’re talking about a government agency this amazing cost-savings option came with a slew of requirements designed to ensure USPS didn’t cannibalize their existing mail volumes.

These requirements mean larger mail formats, which can include brochures, larger envelopes, or booklets, the most common format used is an oversized postcard.  The other notable requirement is that you have to mail to an entire carrier route vs. just specific addresses from a targeted list.

Accordingly, EDDM mailings are a great tool for local serving businesses.  Think pizza shops, automobile dealerships, real estate, healthcare, etc..

Speed (1)

EDDM is about the slowest direct mail format you can use because USPS essentially considers these Marketing Mail class.  There are some ways to reduce the time in transit if certain conditions are met, but these are few and far between.

So if your campaign requires a quick delivery time then you’ll want to consider one of the other options.

Privacy (1)

As detailed, EDDM formats can be envelopes or booklets which would yield a higher privacy score, but given that most EDDM mailings are oversized postcards we’re assigning a score of 1.

Informative (3)

EDDM mailers typically have a decent amount of real estate which gives you “enough” space to include all info desired for the campaign goals.  Different formats and sizing options can reduce or increase the amount of information you can include.

Cost (2)

This score could easily have been a 1, but either way, it’s still one of the most economical mailing options.  The one off-setting consideration that bumped this to a 2 is the oversized requirements that the USPS has.  Larger formats require more consumables which will impact cost, and you have to factor the requirement of mailing to ALL addresses on a carrier route.  The number of addresses on a route can vary but from my experience, a route typically averages around 750.  Multiply that by additional routes needed in your target area and you get a sense of how this can fluctuate.

Engagement (2)

We’re giving EDDM mailers the same score as postcards when it comes to engagement.  While EDDM are bigger than regular postcards they’re still intended to be eye-catching pieces that drive activity elsewhere on websites, landing pages, or even physical locations.


The final mail kit we’re covering today is booklets, also commonly named catalogs.  Catalogs are actually one of the first direct mail campaigns with the likes of Sears and Montgomery Ward sending out countless catalogs featuring all of their products.  Who here still remembers dog-earring and circling their Christmas wish list as a kid?

Just as they were originally, catalogs are still workhorses in today’s direct mail space. They allow companies to visually feature products/services while still having enough space to include detailed information.  This allows consumers to make more informed decisions during their purchasing process.

Speed (2)

Booklets are one of the most labor-intensive direct mail kits because you’re printing multiple pages, collating, folding, binding, and then often sealing them.  While this is very labor intensive you still have the option of choosing the faster first-class mailing.

Privacy (3)

Booklets get the same rating as self-mailers because they’re often partially sealed.  That said, if privacy is what you’re looking for letter mailers would be the direction to go.

Informative (5)

Catalogs are by far the best choice when your campaign has copious amounts of information to share.  They’re also highly variable in page count and page size.  The best catalogs that I’ve seen are those that are designed more like a magazine.  These allow you to develop intriguing stories that draw your reader in and make your brand more sticky.

Cost (5)

More paper and more production is going to push the cost up and make this the most expensive direct mail format featured.  As mentioned previously though, booklets are highly variable so you can do smaller format sizes, fewer pages and marketing mail postage to make your campaign more affordable.

Engagement (4)

By their very nature booklets encourage recipients to at the very least thumb through them which is great for companies that send them out.  They just miss out on getting the top score because letter mailers often include remit envelopes for the recipient to engage.  That said, well-designed booklets will have strong calls to action driving people to your landing page and/or prompting store visits.

Getting Started

The last thing to know when it comes to direct mail formats is that this is just the basics.  Each mail kit has unique options and properties that may or may not benefit your marketing efforts.  That’s where we come in.  Whether you’re ready to move forward with a direct mail campaign, or even if you’re just thinking of it give us a call so we can learn more about your business and then give you ideas for what would work best.