Promo Code Strategy for Postcards: How to Build Offers That Drive Revenue
The offer is the most important variable in a direct mail campaign. A perfect postcard design with a weak offer will underperform a mediocre design with a compelling offer every time. But designing the right offer involves more than choosing a discount percentage — it requires understanding your margins, your customer psychology, your AOV, and the role you want the campaign to play in your retention strategy. This guide covers the mechanics of building effective promo code offers for postcard campaigns.
Offer types and when to use each
Percentage discounts (10–20% off) are the most common and work well for categories with varied price points, since the discount scales with spend. They are less effective when customers are unfamiliar with your price points and cannot calculate the saving. Fixed amount discounts (€10 off, €15 off) work better for AOV-based incentives and feel more tangible — "€10 off your order" is more immediately understandable than "10% off." For win-back campaigns targeting customers who have drifted, a free shipping offer can be surprisingly effective, particularly in markets where shipping costs are a known friction point (Germany, Netherlands). Free gift with purchase appeals strongly to VIP and loyalty segments because it creates a premium feeling without discounting the product itself. Tiered offers ("spend €60, save €10; spend €100, save €20") increase AOV effectively and work well for mid-ticket categories.
Discount depth: how much to offer
The right discount level depends on your gross margin, your campaign goal, and the segment you are targeting. A 10% discount on a 60% gross margin product costs 10 margin points — leaving 50 points to fund the postcard and generate profit. On a 25% gross margin product, 10% off can consume a third of your margin, making the campaign unviable unless average order values are high. Calculate your break-even response rate before setting your discount: break-even responses = campaign cost ÷ (AOV × gross margin ÷ 100 × (1 − discount ÷ 100)). For win-back campaigns, a 15% discount is typically the minimum that drives meaningful response from lapsed customers. For post-purchase thank-you campaigns targeting recent buyers, 10% is often sufficient because the customer is still warm. VIP campaigns should offer something qualitatively different — early access, exclusive products, or a generous loyalty reward — rather than just a deeper percentage.
Expiry windows and urgency mechanics
A promo code with no expiry date converts poorly. Without a deadline, customers file the postcard for "later" and later becomes never. A 30-day expiry is a practical standard for most campaigns — long enough to allow customers time to act, short enough to create genuine urgency. For seasonal campaigns, align expiry with the campaign end (e.g. a summer campaign running until 31 August). For win-back campaigns, a 21-day window creates stronger urgency without feeling aggressive. Consider a two-deadline approach: print the expiry date prominently ("Use before 31 May") but also set up a reminder sequence — if your tools allow, a follow-up postcard or email 5 days before expiry to "last-chance" non-redeemers can recover an additional 10–20% of eventual conversions.
Making promo codes unique and trackable
A shared promo code (e.g. WELCOME15 applied to all 1,000 cards in a campaign) tells you total redemptions but nothing about which customers responded or which postcard version performed. Unique codes per customer (e.g. WB-CUS8821-A) enable individual attribution: you know exactly who redeemed, when, and what they bought. Mayday generates unique promo codes per card automatically and tracks redemptions against the sending customer record in your dashboard. This individual-level data also enables suppression: when a code is redeemed, the customer is automatically excluded from follow-up sequences in the same campaign, avoiding the friction of receiving further "we miss you" postcards after already making a purchase.
Offer strategy for different campaign types
Win-back campaigns (60–120+ days lapsed): use your strongest offer — typically 15–20% off or free shipping — because you are competing with inertia and potentially a competitor relationship. Post-purchase thank-you campaigns (7–30 days post-order): a softer offer (10% off or free shipping on next order) is appropriate — the customer is still warm and does not need a heavy discount to return. Birthday campaigns: the emotional context of a birthday supports a "treat yourself" framing with a 15% or more discount. The personal timing makes the offer feel generous rather than desperate. VIP campaigns: avoid purely transactional discounts. A "first access to our new collection" or "a gift chosen for our best customers" message maintains the premium positioning better than another 10% code. A/B test your offer structure before scaling — the difference between 10% off and €10 off on the same AOV can be a 30–40% difference in response rate depending on your customer base.
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