Summary:
Postcard size influences production cost, mailing eligibility, and marketing effectiveness. Smaller formats like 5.5″ × 4.25″ support cost-effective direct mail campaigns, while larger formats increase visual impact and message capacity. Choosing the correct dimensions early prevents redesign work and ensures compatibility with Canada Post mailing standards. Size selection should align with campaign goals, audience engagement strategy, and design complexity to maximize response rates and production efficiency.
Updated February 2026
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Postcards are a versatile and cost-effective medium for personal and business communication, widely used for marketing, invitations and holiday greetings. They’re typically sent to clients or customers via mail or handed out if too large to mail. In Canada, postcard sizes are regulated by Canada Post, which establishes specific dimensions and mailing requirements to ensure compatibility with their postal systems.
Choosing the right postcard size is crucial not only for optimizing mailing costs but also for effectively conveying your message. Our experts at Little Rock Printing put together a guide to help you decide which postcard size is right for your business needs, along with design and cost considerations.
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Common Postcard Dimensions
Before we dive into the various postcard dimension options, it’s good to know Canada’s post requirements. If you’re mailing a postcard through Canada Post, they must fall within these specifications:
Width: 5.6” to 9.6”
Height: 3.6” to 6.1”
Thickness: at least .009” and no more than .016”
Aspect Ratio: 1:3:1 to 2:6:1
Weight: under 1.7 oz
Now that you know the post requirements, here are some of the most common dimensions used for postcards.
Standard Postcards
- Dimensions: Minimum 5.5” x 3.5” to maximum 6” x 4.25”.
- Postage Cost: Lower postage rates, typically categorized under the “Lettermail” service.
- Usage: Great for minimalist designs for a direct mail marketing campaign, plus it’s affordable and lightweight.
Oversized Postcards
- Dimensions: Larger than 6” x 4.25” and up to 12” x 6”.
- Postage Cost: Higher postage rates, categorized under “Oversized Lettermail” or “Parcel.”
- Usage: Useful for making a bold visual impact or including more detailed content like varied colours and intricate linework.
Custom Sizes
- Dimensions: Any non-standard size outside the above ranges. At Little Rock, we offer custom sizes up to 18” x 12”.
- Postage Cost: May require special handling or parcel rates.
- Usage: Unique designs for niche campaigns or special occasions.
Design & Cost Considerations for Different Sizes
When designing your postcard, you should consider how much information to include on them. This will help determine which size postcard you’ll need to order. The more graphics and information you include the larger your postcard will need to be. Here are some factors to consider when designing your postcard.
Images
High-impact imagery benefits from larger sizes to allow for better detail and visibility. Smaller sizes work best for simple visuals or minimalistic designs.
Text
If detailed information or multiple calls-to-action are necessary, larger sizes are better suited. For concise messages or teaser campaigns, standard sizes are more cost-effective and visually focused.
Target Audience
Larger postcards will grab the attention of your clients and customers and are more effective for audiences that respond to bold visuals. Smaller postcards appeal to audiences that prefer concise, to-the-point messaging.
Mailing Cost Implications
As mentioned above, there are postage costs to consider when choosing your postcard size. Standard size postcards will have a lower postage cost, making them ideal for large-scale campaigns on a budget or if you’re mailing postcards at a high frequency.
Larger sizes will have a higher postage cost or will have to be handed out to your intended audiences; however, you have greater design flexibility and impact. These may be worth the extra cost for a premium campaign or if you’re targeting high-value clients and customers.
Testing Different Formats in Your Marketing Campaigns
If you’re unsure which postcard size is right for your campaign, you could test different sizes and designs to see what your clients and customers respond to better. Here are some different things you can try for the test.
A/B Testing: Test different sizes with the same message to evaluate response rates. Compare standard vs oversized or custom size postcards to identify cost effectiveness.
Analyze Metrics: Use QR codes, custom URLs or trackable phone numbers to measure the success of each format.
Consider Hybrid Campaigns: Start with a large postcard to grab your customer or client’s attention and then follow up with a smaller postcard as a reminder about your campaign or offer.
Print Samples: Test different print designs to ensure the visual elements align with the chosen size and maintain readability.
Print Your Postcards With Little Rock
By aligning postcard size with design priorities and budget considerations, you can optimize your campaign for maximum impact while managing costs effectively. To customize your postcard even more, choose from a variety of paper types.
At Little Rock, we offer 6 paper types varying in thickness and coating so you can choose something totally unique for your campaign. You can even order a free sample paper kit to see which paper type is best for your project. For more details on your postcard order or any other print products we offer, contact the Little Rock Printing experts.
Frequently Asked Questions
How does postcard size affect mailing costs in Canada?
Canada Post pricing tiers are partially based on postcard dimensions and weight. Smaller postcards can often qualify for letter mail rates, while oversized postcards may fall into higher pricing brackets.
Do larger postcards perform better for marketing campaigns?
Oversized postcards often generate higher visibility and engagement because they stand out in mailboxes. However, keep in mind that larger sizes may increase production and mailing costs.
Can I use custom postcard sizes?
Custom sizes are possible, but may affect mailing eligibility and production efficiency. Standard sizes are recommended for most direct mail campaigns.
How do I know which postcard size works best for my campaign?
Campaign goals, budget, and message complexity usually determine postcard size. Promotions with strong visuals benefit from larger formats, while informational campaigns often work best with standard sizes.
Should postcard size influence my design layout?
Yes! Larger formats provide more space for brand imagery and messaging, while smaller postcards require simpler layouts with stronger visual hierarchy.
