Failed Payment / Dunning Subject Lines: 5 Examples (and a Free Tester)

Dunning email interrupts a customer who still wants your product but has a dead card. The subject must convey mild urgency without triggering panic or spam filters — this is a helpful nudge, not a threat.

5 failed payment / dunning subject line examples that work

• your payment didn't go through30 chars
• quick fix: update your card27 chars
• we couldn't process your renewal32 chars
• keep your account active, {first_name}38 chars
• card declined — 30-second fix inside36 chars

Rules for failed payment / dunning subject lines

• Be specific and calm ('your card was declined'), never alarmist or accusatory.
• Reassure that access is still active — fear of loss shouldn't feel like a scare.
• Avoid 'URGENT' and payment-scam vocabulary; it lands in spam and reads as phishing.
• Make the fix one tap ('update card') — friction is why involuntary churn happens.