Postcard Dimensions: Complete Size Guide for Standard, Jumbo & EDDM Postcards

Choosing the right postcard size can make or break your direct mail campaign. Too small and your message gets lost. Too large and you're paying premium postage for wasted space. This guide covers every postcard size option - from standard 4x6 to jumbo EDDM formats - so you can maximize impact while minimizing cost.

Whether you're sending 500 postcards or 50,000, understanding USPS size requirements, postage rates, and design specifications will help you get the best results. At Mail Processing Associates, we've printed and mailed millions of postcards for Florida businesses since 1989, and we're sharing everything we've learned.

Ready to plan your EDDM campaign? Use our free EDDM route planning tool to select carrier routes and get instant quotes.

Standard Postcard Sizes (Mailable Dimensions)

Standard mailing postcards are designed to fit USPS dimensional requirements for the lowest postage rates. Here are the most common postcard dimensions used in direct mail:

*Marketing Mail rate with MPA presorting. First-Class is $0.74 each, or $0.68 presorted (500 piece minimum).

Postcard Size Visual Comparison

Here's how standard postcard dimensions compare to each other at a glance:

4x6 (Postcard rate)          5x7 (Letter rate)
+------------------+         +----------------------+
|                  |         |                      |
|   Standard       |         |                      |
|   photo size     |         |    40% more space    |
|                  |         |                      |
+------------------+         +----------------------+
    4" x 6"                        5" x 7"

6x9 (Letter rate)                 6.25x9 (EDDM eligible)
+----------------------------+    +----------------------------------+
|                            |    |                                  |
|   Maximum standard mail    |    |   Most popular EDDM size         |
|   High visibility          |    |   Stands out in mailbox          |
|                            |    |                                  |
+----------------------------+    +----------------------------------+
         6" x 9"                            6.25" x 9"

4x6 Postcards: The Industry Standard

The 4x6 postcard is the most popular size for direct mail because it:

• Lowest printing cost: Standard photo dimensions = affordable printing
• Same postage as larger sizes: $0.43 with MPA presorting (Marketing Mail)
• Simple to design: Matches common photo ratios, templates widely available
• Sufficient space: Room for headline, image, offer, and CTA
• Cost-efficient at scale: Ideal for 10,000+ piece campaigns

Best uses for 4x6: Appointment reminders, simple promotions, reactivation campaigns, thank-you cards, and any high-volume mailing where cost efficiency matters more than maximum impact.

5x7 Postcards: More Space for Impact

The 5x7 postcard gives you 40% more design space than a 4x6, making it ideal for:

• Multiple images: Show 2-3 products or before/after photos
• More copy: Room for detailed offers, multiple bullet points
• Real estate: Property photos + listing details + agent info
• Events: Date, time, location, RSVP info without crowding
• Premium perception: Larger size = higher perceived value

Good news: With MPA's Marketing Mail presorting, 5x7 postcards mail at the same $0.43 rate as 4x6 - so you get 40% more design space without paying more postage.

6x9 and Larger: Maximum Visibility

Oversized postcards (6x9 and 6x11) stand out in the mailbox and typically generate 20-30% higher response rates than standard sizes. With MPA's $0.43 Marketing Mail rate for all sizes, the only extra cost is printing - making larger formats more affordable than ever.

When oversized makes sense:

• Grand openings: Maximum visibility for your new location
• Major sales events: Room for multiple offers and product images
• New launches: Make a statement with a piece that demands attention
• Political campaigns: Name recognition requires visibility
• High-ticket services: One conversion can pay for the entire campaign

EDDM Postcard Sizes and Requirements (Every Door Direct Mail)

EDDM has different dimensional requirements than standard postcard mail. If you're using Every Door Direct Mail to reach entire neighborhoods without a mailing list, your postcards must meet specific dimensions.

This means standard 4x6 and 5x7 postcards do NOT qualify for EDDM. You need a larger format.

Most Popular EDDM Postcard Dimensions

EDDM postage is just $0.26 per piece (as of 2026), making it one of the most cost-effective ways to reach local audiences. With no mailing list required, you simply select postal routes and reach every residential address.

EDDM advantages:

• No mailing list needed: Reach every home without buying names/addresses
• Lowest per-piece cost: $0.26 beats even bulk mail rates
• Larger format: Minimum size requirements mean your piece stands out
• Route targeting: Select neighborhoods by ZIP code, income, home value
• No permits required: Simple USPS paperwork (we handle it)

USPS Postcard Size Requirements (Official Specifications)

Meeting USPS postal card specifications ensures your postcards qualify for the rates you expect and arrive without delivery issues. Here are the official USPS dimensional requirements:

First-Class Postcard Rate Size Requirements

To mail First-Class ($0.74 each, or $0.68 presorted with 500+ pieces), your mailing piece must meet these dimensions:

• Minimum: 3.5" x 5"
• Maximum: 4.25" x 6"
• Thickness: 0.007" to 0.016"
• Rectangular (length-to-height ratio between 1.3 and 2.5)

Postcards that exceed these dimensions still mail at the same First-Class rate ($0.74 each, or $0.68 presorted).

Postcard Thickness Requirements (Cardstock Weight)

Postcard thickness matters for USPS mail processing equipment acceptance:

Pro tip: We recommend 14pt or 16pt cardstock for all postcards. It meets USPS requirements, feels substantial in hand, and holds up during mail processing.

How to Choose the Right Postcard Size for Your Campaign

The "best" postcard dimensions depend on your campaign goals, budget, and target audience. Use this decision framework to choose:

If Budget Is Your Priority

Choose 4x6. You get the lowest printing cost. With MPA's Marketing Mail presorting, postage is $0.43 for any size up to 6x11 - so you're only saving on print cost, not postage.

Example: Mailing 10,000 postcards at $0.43 each = $4,300 postage (same for 4x6 or 6x9). The printing cost difference is where you save - 4x6 prints cheaper than larger sizes.

If Response Rate Is Your Priority

Choose 6x9 or 6x11. Larger postcards get noticed and generate higher response rates. If you're selling high-ticket items (real estate, home services, automotive), the higher cost per piece is offset by higher conversion value.

If You're Targeting Local Neighborhoods

Choose EDDM (6.25x9 or 8.5x11). At $0.26 per piece with no mailing list required, EDDM is the most economical way to reach every door in specific postal routes. Perfect for restaurants, retail stores, service businesses, and political campaigns.

Recommended Postcard Sizes by Industry

Different industries have different direct mail needs. Here's what works best based on our experience printing and mailing millions of postcards:

Restaurants & Food Service

Recommended: 6.25x9 EDDM

• Large enough to showcase menu items with mouth-watering photos
• EDDM lets you target neighborhoods within your delivery radius
• No mailing list needed - reach every household
• Pro tip: Include a trackable coupon (e.g., "Bring this card for free appetizer") to measure response

Real Estate

Recommended: 6x9 or 5x7

• Space for property photos, listing details, and agent info
• 6x9 fits multiple property images or "Just Sold" announcements
• Pro tip: Use variable data printing to send different listings to different neighborhoods

Home Services (HVAC, Plumbing, Roofing)

Recommended: 6.25x9 EDDM

• Seasonal campaigns (AC tune-ups, heating maintenance) work perfectly with EDDM
• Large size accommodates before/after photos and service pricing
• Pro tip: Mail AC service postcards in April, heating in September - beat the rush

Healthcare & Dental

Recommended: 4x6 for reminders, 5x7 for acquisition

• Appointment reminders and reactivation: cost-efficient 4x6
• New patient specials: 5x7 conveys premium quality
• Pro tip: Include insurance logos if accepted - builds immediate trust

Retail & E-commerce

Recommended: 5x7 or 6x9

• Product showcase postcards benefit from larger sizes
• Sales and new collections need room for multiple product images
• Pro tip: Add a QR code linking to your online store for immediate shopping

Political Campaigns

Recommended: 9x12 EDDM

• Maximum visibility for name recognition
• Largest affordable size helps you stand out during election season
• Pro tip: Front-load your mailings - early impressions stick

Nonprofits & Fundraising

Recommended: 6x9

• Large enough for compelling imagery and storytelling
• Not so large that it seems wasteful of donor dollars
• Include clear CTA and donation URL or QR code
• Pro tip: Personalize with donor name and past giving history for higher response

Timing Your Postcard Mailing Campaign

When you mail your postcards matters almost as much as what size you choose:

• Tuesday-Thursday delivery: Best days for response - avoid Monday mail overload and Friday weekend mindset
• Avoid major holidays: Your postcard gets lost in the shuffle
• Seasonal relevance: HVAC in spring/fall, tax services in Q1, retail before holidays
• Allow lead time: Plan 2-3 weeks from design approval to mailbox arrival
• Consistency wins: Regular touchpoints (monthly, quarterly) outperform one-time blasts

We can help you plan a mailing calendar that maximizes response rates throughout the year. Ask us about scheduling your campaigns.

Postcard Design and Print Specifications

Understanding bleed, trim, and safe zones ensures your postcard artwork prints correctly without white edges or cut-off text.

Bleed Area

Bleed is the area beyond the trim line where your design extends. This ensures colors and images reach the edge with no white borders.

• Standard bleed: 0.125" (1/8 inch) on all sides
• For a 4x6 postcard, your design file should be 4.25" x 6.25"
• Extend background colors and images into the bleed area

Print-Ready File Dimensions (with Bleed)

When setting up your postcard design file, use these dimensions to account for bleed and safe zones:

Safe Zone

Keep all important text and logos at least 0.125" inside the trim line. This prevents accidental cutting of critical elements.

Resolution and File Format

• Resolution: 300 DPI minimum for sharp printing
• Color mode: CMYK (not RGB)
• File format: PDF preferred, also accept AI, PSD, or high-res JPEG

Postcard Paper Stock and Finish Options

The paper stock and finish you choose affects how your postcard feels in hand, how vibrant colors print, and how recipients perceive your brand quality.

Paper Weight (Thickness)

Coating Options

Pro tip: For most direct mail campaigns, we recommend 14pt gloss UV or 14pt matte. Both meet USPS requirements, look professional, and are cost-effective at scale.

Specialty Options

• Spot UV: Glossy coating on specific areas (logo, product image) - creates eye-catching contrast
• Foil stamping: Metallic gold, silver, or copper accents - premium luxury feel
• Die-cutting: Custom shapes (rounded corners, unique silhouettes) - stands out from rectangular mail
• Variable data printing: Personalize each postcard with recipient name, custom offers, or property images - significantly boosts response rates
• Embossing/debossing: Raised or recessed elements - tactile impact that gets noticed

Postcard Postage Rates by Size (2026 USPS Rates)

Understanding postcard mailing costs helps you budget accurately. Here are current 2026 USPS postage rates by mail class and size:

MPA advantage: Our presorting gets you the $0.43 Marketing Mail rate on any postcard size up to 6x11. No permit needed - we handle everything.

Total Cost Comparison: 5,000 Postcard Campaign

Here's what a typical 5,000-piece postcard mailing campaign costs, including printing and postage:

*Printing estimates based on 14pt gloss, 4/4 color. Actual pricing varies by quantity, paper stock, and finishing. Get exact pricing for your project.

Key insight: EDDM at 6.25x9 costs significantly less per piece than standard 4x6 mailing - you get a larger postcard for less money when targeting entire neighborhoods.

Tracking Your Postcard Direct Mail Results

Measure your postcard campaign's success with these proven tracking methods:

• Unique promo codes: "Use code POSTCARD10 for 10% off"
• Dedicated phone numbers: Track calls from your postcard specifically
• QR codes: Link to a campaign-specific landing page
• Unique URLs: mailpro.org/spring-sale tracks postcard visitors
• Ask customers: Simple "How did you hear about us?" at checkout

Advanced tracking: We can set up variable data printing with unique codes for each recipient, enabling precise tracking of who responded to your mailing.

Expected Response Rates by Postcard Size

Industry direct mail benchmarks to help set realistic campaign expectations:

Response rates vary significantly based on offer strength, list quality, design, and industry. These are averages - your results may be higher or lower.

How to beat the averages:

• Use a targeted list (not just saturation)
• Include a compelling, time-limited offer
• Make the call-to-action unmissable
• Test different headlines and offers (A/B testing)
• Follow up - multiple touches increase response

Common Postcard Size Mistakes (And How to Avoid Them)

After printing millions of postcards, we see these errors regularly. Avoid them to save time, money, and frustration:

Mistake #1: Using 4x6 or 5x7 for EDDM

The problem: You design a beautiful 5x7 postcard, submit it for EDDM, and it gets rejected. Why: EDDM requires postcards larger than 6.125" on at least one dimension. Standard 4x6 and 5x7 don't qualify. Solution: Use 6.25x9 minimum for EDDM campaigns.

Mistake #2: Forgetting to Add Bleed

The problem: Your printed postcards have white edges or your logo gets cut off. Why: You designed at exact finished size without accounting for cutting tolerance. Solution: Add 0.125" bleed on all sides and keep important elements 0.125" inside the trim line.

Mistake #3: Choosing Size Based Only on Postage

The problem: You always pick 4x6 to save $0.20 per piece, but response rates disappoint. Why: Smaller postcards get less attention. Solution: Calculate expected ROI, not just cost. A 6x9 with 25% higher response often outperforms a cheaper 4x6.

Mistake #4: Ignoring Thickness Requirements

The problem: Your postcards get returned or charged letter rates. Why: USPS requires minimum 0.007" thickness (14pt cardstock). Solution: Always use 14pt or thicker. Bonus: thicker stock feels more professional and gets better response.

Mistake #5: Designing Without Mailing Panel Specs

The problem: Your postcards aren't delivered or get returned for postage due. Why: USPS requires specific address and indicia placement - you can't use the entire back for design. Solution: Reserve the right half of the address side for the mailing panel, or use our templates that include the correct placement.

Postcard Sizes FAQ

Are postcards 4x6 or 5x7?

Both are standard sizes. With MPA's Marketing Mail presorting, both mail at the same $0.43 rate - so choose based on design needs, not postage cost. 4x6 has lower printing costs; 5x7 gives you 40% more space.

What size postcard for EDDM?

EDDM postcards must be larger than 6.125" x 11.5" on at least one dimension. Popular EDDM sizes are 6.25x9, 6.25x11, 8.5x11, and 9x12. Standard 4x6 and 5x7 do NOT qualify.

What is the cheapest postcard size to mail?

With MPA's Marketing Mail presorting, all postcard sizes up to 6x11 mail at $0.43 each. EDDM is even cheaper at $0.26/piece but requires minimum 6.25x9 size.

Can I use a 5x7 postcard for EDDM?

No. 5x7 is too small for EDDM requirements. You need at least 6.25x9 or another size that exceeds 6.125" on one dimension.

What cardstock weight should I use?

We recommend 14pt or 16pt cardstock for most postcards. This meets USPS thickness requirements (0.007" minimum) and provides a professional feel.

How much does it cost to print postcards?

Printing costs vary based on quantity, size, and paper stock. For 5,000 4x6 postcards on 14pt stock, expect roughly $0.05-0.10 per piece. Contact us for exact pricing on your specific project.

Which postcard size gets the best response rate?

Larger postcards (6x9, 6x11) typically generate 20-30% higher response rates because they stand out in the mailbox. However, 4x6 offers better cost efficiency for high-volume campaigns.

What is bleed on a postcard?

Bleed is the extra 0.125" of design that extends beyond the trim line. It ensures your colors and images go to the very edge with no white borders after cutting.

What are the mailing panel requirements?

USPS requires a clear mailing panel on the address side. Reserve the right half for the address and postage indicia. The left half can contain your return address and a brief message.

What DPI should my design be?

Use 300 DPI for print-quality images. Lower resolution will look pixelated. Also use CMYK color mode (not RGB) for accurate color reproduction.

Should I use EDDM or targeted mailing?

Choose EDDM when you want to reach every household in specific neighborhoods (restaurants, retail, local services). Choose targeted mailing when you have a specific customer list or demographic criteria. Targeted costs more but reaches your ideal customers directly.

Where do I get a mailing list?

You have several options:

• Your own customer list: Past customers, email subscribers, leads
• Purchase a list: We can provide targeted mailing lists based on demographics (age, income, homeowner status), geography, and business type
• EDDM (no list needed): Reach every address on selected postal routes without buying names
• List brokers: Third-party providers offering specialized lists

Pro tip: Renting a list is often more cost-effective than buying. You pay per use and get fresh, updated data each time.

Ready to Print Your Postcards? Let's Get Started.

Mail Processing Associates has been helping Florida businesses with direct mail services and commercial postcard printing since 1989. We handle everything from design to delivery, ensuring your postcards meet USPS requirements and reach your audience on time.

Our postcard services include:

• Custom design and template setup
• High-quality offset and digital printing
• EDDM campaign management
• Variable data printing for personalization
• Mailing list services and data processing
• Complete fulfillment and USPS drop-off

Next Step: Now that you know the size requirements, plan your EDDM campaign with our free tool.

Related Guides

Dive deeper into direct mail strategy with these resources:

• How Much Do Postcards Cost? - Complete pricing breakdown for printing and mailing
• What Is Every Door Direct Mail (EDDM)? - Beginner's guide to EDDM campaigns
• EDDM Design Tips - Create postcards that get results
• Best Paper Finishes for Direct Mail - Gloss, matte, and specialty options
• USPS Direct Mail Postage Rates Explained - Current rates and how to save
• UV Coating for Postcards - When and why to add protective coating