Choosing the right format for a direct-mail campaign is about balancing impact with cost. In 2026, budget pressures and sustainability expectations mean marketers must be smarter about format selection: pick what drives the action you need, not what simply looks expensive. Here’s a practical guide to the most cost-effective options and when to use them.
Postcards — big value for small spend
Postcards remain the most cost-efficient format for short, urgent messages. A6 or A5 postcards are cheap to print, quick to personalise and often qualify for favourable bulk postage rates. Use postcards for event reminders, quick offers, local door drops or follow-ups where the message is short and the CTA is simple (QR code, short URL, promo code). They’re ideal for testing creative and timing cheaply — run A/B postcard pilots to find the best headline or offer before scaling.
Letters & DLs — personal but still economical
A personal letter in a DL envelope is perceived as higher value than a postcard but can still be cost-effective if kept lean. Use letters for renewals, invoices, membership asks and messages that require a more formal tone. Folding an A4 sheet into DL keeps print costs down while giving you room for personalised variable content. For better ROI, keep the copy focused and include a single, trackable CTA.
Multi-piece packs — invest where the lifetime value justifies it
Multi-piece mail packs (letter + brochure + coupon, or prospectus packs) create a premium unboxing experience and significantly increase dwell time. They work best when the expected lifetime value (student tuition, high-value customer, major donor) justifies higher per-piece costs. To keep packs cost-effective: limit heavy inserts, use smart variable printing to reduce wasted content, and choose mail-ready packaging that’s machine-friendly to avoid hand-assembly surcharges.
When non-standard or premium formats make sense
Square mail, folded brochures, or tactile finishes grab attention — but they often carry higher postage or handling fees (non-machinable surcharges). Reserve premium formats for targeted VIP lists, retention programmes or reactivation of high-value customers where a stronger emotional response is needed.
Postage and production trade-offs
Size, weight and machinability determine postage bands. A lightweight A5 pack might stay in a favourable band, while thicker or oddly shaped pieces move you into a more expensive category. Factor postage early in format decisions and model cost-per-response rather than just cost-per-piece. Sometimes a cheaper format with a higher response rate delivers better ROI than a pricier pack with low conversion.
Sustainability and perception
In 2026, audiences notice environmental choices. Choose FSC or recycled stocks, reduce unnecessary plastic, and highlight eco credentials on the piece. Sustainable choices can be a selling point — and often a procurement requirement in public and corporate sectors.
Test, track and scale
Always pilot different formats. Use PURLs, QR codes and unique offer codes to attribute response, and compare true cost-per-acquisition across formats. Small pilots reduce risk and give clear evidence for investment decisions.
How Herald Chase can help
If you’d like help modelling formats against expected response and postage, or you want a sample pack to check finishes and sizes, book a free campaign review with our team at www.heraldchase.com — we’ll map the most cost-effective format for your objectives and budget.
