Choosing a Mailer Type
What it is
thanks.io offers five mailer types. Each one has a different physical format, price point, and ideal use case. Picking the right type before you design saves time and ensures your mail lands the way you intend.
Mailer comparison
| Type | Size / Format | Best for | Stamp type | First Class option |
|---|---|---|---|---|
| Postcard 4×6 | 4 × 6 in | High-volume outreach, promotions | Metered | Yes |
| Postcard 6×9 | 6 × 9 in | Neighborhood farming, real estate | Metered | Yes |
| Postcard 6×11 | 6 × 11 in | Bold visuals, maximum print area | Metered | Yes |
| Letter (windowed) | 8.5 × 11 in | Formal communications, B2B | Metered | Yes |
| Letter (windowless) | 8.5 × 11 in | Full-bleed design, newsletters, PDFs | Metered | Yes |
| Notecard | 5 × 4 in folded | Premium touches, VIP clients | Real stamp | Yes |
| Gift Card | Branded card | Appreciation, win-back, gifting | Real stamp | Yes |
| MagnaCard | 6 × 9 in magnetic | Staying power - sticks to fridges | Metered | Yes |
For current per-piece pricing on each type, see thanks.io/pricing.
When to pick each type
4×6 Postcard - Your go-to for cost-efficient, high-volume sends. Great for e-commerce post-purchase thank-yous, drip campaigns, and lead follow-up.
6×9 Postcard - More visual space than 4×6 with a stronger presence in the mailbox. Popular for real estate neighborhood farming, local service businesses, and promotions.
6×11 Postcard - Maximum postcard real estate. Use it when your design needs room - event announcements, luxury brands, or campaigns where standing out is the priority.
Windowed Letter - The recipient's address shows through a window in the envelope. Best for formal, professional communications. Commonly used by nonprofits, financial services, and B2B outreach.
Windowless Letter - A full-bleed printed letter with complete design control. Supports multi-page PDFs. Use it for newsletters, long-form content, or any letter where you want full design freedom.
Notecard - A 5.5x8.5 folded card with a real postage stamp. The most personal-feeling format. Use it for VIP client touches, post-meeting thank-yous, and high-value relationship moments.
Gift Card - A branded gift card delivered by mail with a real postage stamp and QR code for redemption. Use it for customer appreciation, win-back offers, and gifting. Note: Gift Cards are exempt from Duplicate Prevention.
MagnaCard - A 6×9 postcard on magnetic stock. It adheres to refrigerators and metal surfaces, giving it significantly longer staying power than paper mail. Best for local businesses that want their contact details on display for months.
Tips & best practices
- If cost per piece is your primary constraint, start with the 4×6 postcard.
- If you want the recipient to keep your mail long-term, use a MagnaCard or Notecard.
- For trust-building with cold contacts, a windowed letter feels more formal than a postcard.
- Gift Cards generate unusually high response rates because recipients must act to redeem them.
- All types support handwritten-style messages - choose AI Fonts and optional Realism Mode to maximize the personal feel.