Postcards sizes

Whether you’re promoting a local event, adding thank-you offers to customer purchases or simply sending a thoughtful note to a friend, a custom postcard can be your best ally – and choosing the right postcard size can make all the difference. In this guide, we’ll walk you through the most common postcard sizes, their typical uses and how to pick the one that best fits your needs.

Standard Postcard Sizes in the UK

There’s more than one “standard” when it comes to postcard dimensions. Each size offers something different in terms of design space, visual impact and cost.

Here are the most popular UK postcard sizes:

• A6 (105 x 148 mm): The classic choice. Compact and versatile, this is ideal for thank you notes, event reminders or simple promos.
• A5 (148 x 210 mm): A larger format with more room for bold graphics or detailed messaging.
• A4 (210 x 297 mm): Great for poster-style designs, menus or large-scale promotional materials.
• DL (99 x 210 mm): Sleek and slim. Popular for direct mailers or formal invites.
• Small square (148 x 148 mm): A modern, eye-catching format for personal or creative branding.
• Large square (210 x 210 mm): Bigger and bolder – ideal when you want your postcard to feel more like a statemen

Why size is important

The size of your postcard affects more than just the design – it impacts how your message is received, how much information you can include and even how much it costs to print and post.

• Messaging: Smaller postcard sizes like A6 are ideal for short messages or limited-time offers. Larger formats (A5 and A4) give you room for extra details or visual storytelling.
• Design flexibility: More space allows for larger text, multiple images or more creative layouts.
• Budget and delivery: Bigger cards may cost more to print and post. A6 is typically the most cost-effective option, while A4 gives you more visual impact at a higher price point.

Choosing the right postcard size

Not sure which size is right for you? Here’s a breakdown that can help you decide:

1. A6: Perfect for promo codes, thank you notes, save the dates or appointment reminders. Easy to carry and budget-friendly.
2. A5: Great for event invitations, new product launches or seasonal promos where you need more room to explain (or show off).
3. A4: Ideal for newsletters, open house invites or promotions that require space to shine.
4. DL: A popular choice for direct mail campaigns – especially when paired with envelopes or folded leaflets.
5. Square (148 x 148 mm): Adds a modern twist to your message; perfect for lifestyle brands, photographers or creative small businesses.
6. Square (210 x 210 mm): High-impact option when you want to turn heads or leave a lasting impression.

How to make it uniquely yours

Once you’ve picked your ideal postcard size, make it yours with custom finishes. Choose from gloss, matte or soft-touch papers, add smooth round corners for a subtly modern look, or place a QR code on the back – the options are wide open. Got more to share? Go for double-sided printing for extra space. It’s all about giving your message the room – and the style – it deserves.

Final thoughts

Postcards may be small, but used properly, they can make a big impact – especially when you choose the right size for the job. Whether you’re sending a warm thank you, running a campaign or spreading the word about a new product, picking the right format helps your message land exactly as you intended.