EDDM Postcard Sizes: Complete Size Requirements Guide
Choosing the right EDDM postcard sizes is one of the most important decisions you will make when planning an Every Door Direct Mail campaign. USPS has strict dimension requirements that your mailpiece must meet to qualify for the discounted EDDM postage rate of $0.26 per piece. Get the size wrong and your postcard ships at standard First-Class rates instead - nearly double the cost.
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This guide covers every USPS size requirement for EDDM, compares the most popular postcard dimensions, and helps you choose the best size for your business goals and budget. Whether you are mailing your first EDDM campaign or optimizing an ongoing program, understanding these specifications will save you money and prevent costly mistakes at the post office.
USPS EDDM Size Requirements
To qualify for EDDM postage at $0.26 per piece, your mailpiece must meet specific size requirements set by the United States Postal Service. These requirements exist because EDDM is classified as a "flat" - a category of mail larger than standard letters and postcards. Understanding these EDDM postcard sizes requirements is essential before you invest in design and printing.
A mailpiece must meet at least one of these three minimum dimension requirements to qualify for EDDM:
- Length greater than 10.5" - The longest side of your mailpiece exceeds 10.5 inches
- Height greater than 6.125" - The shorter side of your mailpiece exceeds 6.125 inches
- Thickness greater than 0.25" - Your mailpiece is thicker than a quarter inch (useful for booklets or multi-page pieces)
Your mailpiece only needs to exceed one of these three dimensions, not all three. However, most EDDM postcards qualify by exceeding both the height and length minimums, which gives you a flat mailpiece with plenty of design space.
Maximum dimensions: 12" x 15". Maximum weight: 3.3 oz. Any mailpiece exceeding these limits will not qualify for EDDM and will be returned or charged at a higher rate. Be sure to weigh your finished piece, especially if using heavy cardstock or coatings.
These size requirements apply to all EDDM mailpieces, whether you are using EDDM Retail (dropping off at the post office yourself) or EDDM BMEU (using a commercial mail entry unit). For a full breakdown of what you will pay per piece, see our current EDDM postage rates guide.
Common EDDM Postcard Sizes
While USPS allows any dimensions within the minimum and maximum range, certain EDDM postcard sizes have become industry standards. Printers stock these sizes, which means faster turnaround times and lower costs. Choosing a standard size also ensures your postcard fits properly in mail carrier trays and residential mailboxes.
Here are the six most popular EDDM postcard sizes used by businesses across every industry:
6.125" x 11" - Minimum Qualifying Size
The 6.125" x 11" postcard is the smallest flat that meets EDDM requirements. It exceeds both the 6.125-inch height minimum (barely) and the 10.5-inch length minimum. This size is the most cost-effective option because it uses the least paper and is the lightest, keeping printing and postage costs at their absolute minimum. It provides enough space for a bold headline, a single offer, and contact information.
6.5" x 9" - Popular Compact Option
The 6.5" x 9" postcard exceeds the 6.125-inch height minimum while staying compact. This size is extremely popular with restaurants, retail stores, and service businesses running regular promotions. It feels substantial in the hand without being oversized, and the slightly wider format gives you a nice landscape layout for images and text side by side.
8.5" x 11" - Letter-Size Flat
At standard letter size, the 8.5" x 11" flat gives you significantly more design space than smaller options. This size works well for businesses that need to communicate detailed information - think restaurant menus, service lists, real estate listings, or healthcare provider introductions. The familiar letter-size format also lends a professional, authoritative feel to your mailing.
9" x 12" - Large Format
The 9" x 12" postcard is a favorite for real estate agents, home service companies, and anyone who wants maximum visual impact. This size dominates the mailbox, making it nearly impossible to overlook. It provides ample room for large property photos, before-and-after comparisons, or detailed maps showing your service area.
11" x 17" Folded to 11" x 8.5" - Bifold Option
For businesses that need even more content space, an 11" x 17" sheet folded in half creates a bifold mailer at 11" x 8.5". This gives you four panels of content - perfect for restaurant menus, product catalogs, real estate brochures, and detailed service guides. The folded format also adds a sense of discovery as recipients open the piece.
12" x 15" - Maximum EDDM Size
The largest mailpiece USPS allows for EDDM, the 12" x 15" flat makes a dramatic impression. This size is typically reserved for special campaigns like grand openings, major sales events, or high-value real estate listings. While printing costs are higher, the sheer visual dominance of this format can justify the investment for the right campaign.
| Size | Type | Best For | Cost Impact |
|---|---|---|---|
| 6.125" x 11" | Minimum flat | Budget campaigns, simple offers | Lowest cost |
| 6.5" x 9" | Compact flat | Restaurants, retail, promotions | Low cost |
| 8.5" x 11" | Letter-size flat | Menus, service lists, healthcare | Moderate cost |
| 9" x 12" | Large flat | Real estate, home services | Moderate-high cost |
| 11" x 17" folded | Bifold mailer | Menus, catalogs, brochures | Higher cost |
| 12" x 15" | Maximum flat | Grand openings, luxury real estate | Highest cost |
For a detailed look at printing and postage costs for each of these sizes, see our complete EDDM cost breakdown.
EDDM vs Standard Postcard Sizes
One of the most common questions businesses ask is whether they can use standard postcards - like the familiar 4" x 6" or 5" x 7" - for EDDM campaigns. The answer is no. Standard postcards do not meet EDDM minimum size requirements, and this distinction has a significant impact on both cost and strategy.
A standard 4" x 6" postcard measures only 4 inches in height and 6 inches in length. Both dimensions fall well below the EDDM minimums of 6.125 inches in height and 10.5 inches in length. Similarly, a 5" x 7" postcard misses both thresholds. These smaller postcards must be mailed as First-Class Mail at $0.56 per piece or Marketing Mail at approximately $0.43 per piece - significantly more expensive than EDDM's $0.26 rate.
The trade-off is clear: EDDM requires larger mailpieces, but you save substantially on postage. For a 5,000-piece campaign, the difference between First-Class postcard postage ($0.56) and EDDM postage ($0.26) is $1,500 in savings. That savings more than covers the slightly higher printing cost of the larger EDDM postcard sizes.
The larger EDDM format is actually a design advantage. More space means bigger headlines, more compelling images, and room for a clear call-to-action. Studies consistently show that larger mailpieces get higher response rates than smaller postcards.
If you are already planning to send larger postcards, EDDM gives you a significant postage discount. And if you are used to sending small postcards, switching to EDDM-qualifying sizes and using the EDDM program often costs less overall despite the larger print size. Check the current EDDM postage rates for the latest pricing.
Thickness and Weight Requirements
Beyond height and length, USPS also has thickness and weight requirements for EDDM mailpieces. While most standard postcard stock easily meets these requirements, it is important to verify your specifications - especially if you are using unusual materials, adding inserts, or applying heavy coatings.
Minimum thickness: 0.007" - This is the thinnest your mailpiece can be. Standard postcard stock far exceeds this minimum. For reference, a sheet of copy paper is approximately 0.004 inches, so even relatively thin cardstock qualifies.
Maximum weight: 3.3 oz - Your finished mailpiece, including any coatings, inserts, or attached items, cannot exceed 3.3 ounces. Standard postcards weigh well under this limit, but multi-page folded pieces or oversized formats with heavy cardstock should be weighed before production.
Recommended Paper Stock
The most common paper stocks used for EDDM postcards are:
- 14pt cardstock (0.014" thick) - The industry standard for EDDM postcards. Provides excellent durability, a professional feel, and meets all USPS thickness requirements. This is the most cost-effective option for most campaigns.
- 16pt cardstock (0.016" thick) - A premium option that feels noticeably thicker and more substantial. Ideal for luxury brands, high-value offers, or when you want your mailpiece to stand out by feel alone.
Coating Options
Coatings protect your postcard and enhance its appearance. All standard coatings are compatible with EDDM requirements:
- UV coating - High-gloss finish that makes colors pop and adds durability. Best for photo-heavy designs.
- Aqueous coating - Water-based protective coating with a subtle sheen. Environmentally friendly and cost-effective.
- Matte coating - Smooth, non-reflective finish with an elegant appearance. Easy to write on, making it ideal for postcards with fill-in areas like coupon codes.
Any of these coatings will keep your finished mailpiece well within the 3.3-ounce weight limit for standard EDDM postcard sizes.
Which EDDM Size Should You Choose?
Selecting the right EDDM postcard size depends on your budget, your message complexity, and your industry. Here is practical guidance to help you make the best choice for your specific situation:
Budget-Conscious Campaigns: 6.125" x 11"
If cost is your primary concern, the 6.125" x 11" postcard is your best bet. It qualifies for EDDM at the minimum size, which means the lowest possible printing cost per piece. This size works well for simple promotions, appointment reminders, and single-offer campaigns. You have enough space for a strong headline, one hero image, and a clear call-to-action.
Maximum Visual Impact: 8.5" x 11" or 9" x 12"
When you need your mailpiece to command attention, step up to the 8.5" x 11" or 9" x 12" format. These larger EDDM postcard sizes dominate the mailbox and give you room for compelling visual storytelling. The extra design space lets you include multiple images, detailed service descriptions, maps, and testimonials - all while maintaining clean, uncluttered layouts.
Restaurant Menus: 8.5" x 11" or 11" x 17" Folded
Restaurants have unique needs because they typically want to show their menu alongside promotions. The 8.5" x 11" size fits a condensed menu with a feature offer, while the 11" x 17" folded bifold gives you four full panels - enough for your complete menu, an introductory offer, your location map, and ordering information.
Real Estate: 9" x 12"
Real estate agents consistently choose the 9" x 12" size because it showcases property photos at their best. The larger format lets you feature one or two hero property images at a size that shows real detail - room interiors, exterior architecture, and neighborhood views all look impressive at this scale. Include your headshot, contact information, and recent sales stats for a complete marketing piece.
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Frequently Asked Questions
What is the minimum size for EDDM?
To qualify for EDDM postage rates ($0.26 per piece), your mailpiece must exceed at least one of these three minimum dimensions: height greater than 6.125 inches, length greater than 10.5 inches, or thickness greater than 0.25 inches. Most EDDM postcards qualify by exceeding both the height and length minimums. The most common minimum-qualifying size is the 6.125" x 11" postcard.
Can I use a 4x6 postcard for EDDM?
No. Standard 4x6 postcards do not meet EDDM minimum dimension requirements. A 4x6 postcard is only 4 inches in height and 6 inches in length, falling well short of both the 6.125-inch height minimum and the 10.5-inch length minimum. The smallest EDDM-qualifying postcard size is 6.125" x 11". If you want to send 4x6 postcards, you will need to use First-Class Mail at $0.56 per piece instead of EDDM's $0.26 rate.
What is the maximum EDDM size?
The maximum size for an EDDM mailpiece is 12 inches by 15 inches, with a maximum weight of 3.3 ounces. Any mailpiece exceeding these dimensions or weight will not qualify for EDDM postage rates and will either be returned or charged at a higher postage rate. Always weigh your finished piece before committing to a full print run.
Does postcard thickness matter for EDDM?
Yes, EDDM mailpieces must be at least 0.007 inches thick. Standard 14pt cardstock measures approximately 0.014 inches, which comfortably exceeds this minimum requirement. Thickness can also be used as the sole qualifying dimension - if your mailpiece is thicker than 0.25 inches (such as a booklet or multi-page piece), it qualifies for EDDM even if it does not meet the height or length minimums.
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