To write a postcard, divide the back of the card into two halves. On the left side, write your date, greeting, message, and signature. On the right side, write the recipient's full name and mailing address. Place a stamp in the top-right corner. Leave the bottom ⅝ inch of the back clear for the postal barcode. Drop it in a USPS collection box without the need for an envelope.

Postcards are one of the simplest forms of written communication, but getting the layout right matters. A misplaced address or stamp can result in undeliverable mail. This guide covers everything you need: the correct postcard format, how to address a postcard, what to write in your message, USPS size requirements, and postcard examples you can use right away.

TL;DR

• Write the return and recipient's address on the blank (address) side of the postcard.
• Use the bottom-left area to write your message.
• The top-right corner of the postcard is reserved for the postal stamp.
• Always leave the bottom ⅝ inch of the address side clear for the USPS routing barcode.

Key Takeaways

• Postcards travel without an envelope, but USPS sorting machines route by ZIP.
• Only rectangular cards between 5-by-3 1/2 inches and 6-by-4 1/4 inches qualify for the standard postcard rate.
• Drafting the recipient's address before writing the message prevents you from running your note into the right-hand address zone, the most common cause of misdelivery.
• Use a ballpoint pen — gel pens and markers smear during mail sorting, while ballpoint ink dries fast and survives handling.
• Treat postcards as public mail: anyone touching the card can read it, so never include account numbers, passwords, or sensitive personal details.

Sending a postcard overseas follows the same left/right layout. The difference is in the address format on the right side. Add the destination country on the final line, written in English (or in both English and the local language), in capital letters.

Recipient Full Name
Street Address
City, Postal Code
COUNTRY (in capital letters)

For example, a postcard sent to the United Kingdom would end with UNITED KINGDOM on the last line. For Canada: CANADA. For Australia: AUSTRALIA.

 Also Read: How to Write a UK Address on an Envelope

Tips for international postcards:

• Purchase international postage at your local post office, as standard postcard stamps are domestic only.
• Write clearly and use block capital letters for the address to reduce misrouting.
• Delivery times vary widely: one to two weeks for most destinations, longer for remote areas.
• USPS international postcard rates vary by destination country; check USPS.com for current pricing before mailing.

 Also Read: Direct Mail Postcard Examples for Your Marketing Campaign

To qualify for standard postcard postage rates in the US, your postcard must meet USPS dimensional requirements. Cards outside these dimensions are classified as letters or large envelopes and charged at higher rates.

Key rules:

• Postcards must be rectangular, as square postcards incur non-machinable surcharges.
• The card must be at least 0.007 inches thick (cardstock weight).
• Oversized, vertical, or unusually shaped cards are charged at standard letter rates.
• Do not write or place stickers in the bottom ⅝ inch; this is the USPS barcode zone.

A standard postcard stamp covers domestic delivery within the US. Current postcard stamp rates are set by USPS and updated periodically. Check store.usps.com for the current price before purchasing. For context, postcard stamps are consistently cheaper than first-class letter stamps, making postcards one of the most affordable forms of physical mail.

💡Also Read: Expired Listing Postcards

How to Write a Postcard Message?

Postcard messages work best when they are short, warm, and specific. You have limited space; roughly 5 to 8 sentences, depending on your handwriting. So, every line should count.

Postcard Message Structure

Date and Location

Write the date and the place you are writing from in the top-left area, below the return address. For example: July 4, 2026 – San Francisco, CA. You can skip the location if it is already in your return address.

Greeting

Open with a personalized greeting. Using the recipient's name adds warmth. Examples: Dear Emma, / Hi David, / Greetings from Paris, Mom!

Your Message (2 – 5 sentences)

Keep it specific and personal. Mention where you are, something you saw or did, the weather, the food – one vivid detail is better than a generic overview. Avoid trying to summarize an entire trip; pick one moment.

Closing Line

A brief, warm sign-off works well: Wish you were here! / See you soon. / Thinking of you. / Miss you already.

Signature

Sign with your name or a nickname the recipient will recognize. Keep it brief: Love, Sarah / – Alex / Warmly, James

What to Write on a Postcard: Tips

• Write the address first: this ensures you leave enough space on the right side and don't accidentally spill your message into the address zone.
• Use a ballpoint pen: gel pens and markers smear during mail handling. Ballpoint ink dries quickly and holds up during sorting.
• Avoid sensitive information: postcards travel unsealed, so anyone handling them can read the content. Never include bank details, passwords, or other private information.
• Keep your message to the left side: writing into the right (address) half can cause misdelivery or rejection.
• Write clearly: illegible handwriting in the address area is one of the most common causes of undeliverable postcards.

Postcard Message Examples

Travel Postcard

July 3, 2026 · Rome, Italy

Dear Mom,

I made it to Rome! The Colosseum is even bigger than I imagined, and I ate the best pasta of my life last night in Trastevere. The weather is warm and sunny. Wishing you were here to share the gelato.

Love, Sarah

Birthday Postcard

Dear Marcus,

Wishing you a wonderful birthday! I hope today brings you good food, great company, and a little bit of adventure. You deserve all of it. Let's catch up soon – it's been too long.

Warmly, James

Holiday / Seasonal Postcard

December 2026

Hi Emma,

Sending you warm wishes from a very snowy Chicago. The kids are thrilled – we built a snowman that's nearly as tall as the front door. Hope your holiday season is restful and full of joy.

Merry Christmas – The Hoffmanns

“Thinking of You” Postcard

Hi Claire,

I walked past that coffee shop on 5th where we used to meet and thought of you immediately. Hope life is treating you well. Long overdue for a proper catch-up – let me know when you're free.

Miss you – Tom

Things to Keep in Mind

• Postcards are open mail. So, do not write personal details like bank account numbers, social security numbers, or passwords. Anyone handling the card can read it.
  
• Keep your message on the left side. If your writing crosses into the right (address) half, it can cause confusion and result in misdelivery.
  
• If you want to write a longer personal message, consider a letter in an envelope instead.
  
• You can write on the front of a postcard too, but keep in mind that the image side typically has very limited writing space.
  

How to Send a Postcard

Once your postcard is written, addressed, and stamped, you have two options:

• Drop it in a USPS blue collection box: These are found on street corners, in post offices, and outside many businesses. No postage or envelope is needed – just drop it in.
• Hand it to a postal clerk at your local post office: This is the better option if you are unsure about the correct postage (especially for heavier or oversized cards) or if you are sending internationally.

If you are traveling, most hotels will accept postcards at the front desk and arrange to mail them for you, especially in tourist destinations.

 Also Read: What Does Not Deliverable as Addressed Mean (UAA)?

Why Do People Still Send Postcards?

In an era of instant messaging and social media, postcards remain uniquely meaningful. They require deliberate effort, choosing a card, writing by hand, addressing, stamping, and mailing. That effort is visible to the recipient. A postcard says: I thought of you specifically, and I took time to say so.

They are also persistent. Unlike a text or a social post, a postcard is a physical object someone can keep. Many people pin them to bulletin boards or keep them in shoeboxes for years. Postcards show up in the physical world, in a mailbox, where almost nothing personal arrives anymore, and that novelty gives them outsized emotional weight relative to their size.

The format's constraints are also its strength. Limited space forces clarity and warmth. There is no room for lengthy explanations or complicated sentiments, only the most essential thing you wanted to say.

Why Businesses Should Consider PostGrid to Send Postcards at Scale?

Hand-addressing works for a holiday card to a friend, but breaks down fast for appointment reminders, renewal notices, win-back campaigns, or event invites going to thousands of recipients.

PostGrid's Postcard API automates the printing, addressing, and mailing process and includes CASS-certified address verification to reduce undeliverable mail. This guide covers personal postcard writing for business mailing workflows.

Sign up now to automate and send postcards at scale.

💡Also Read: Where to Buy Stamps