Shopify app · Margin recovery
OverlayIQ blocks repeat discount usage at checkout using device fingerprinting, address matching, and behavioral signals — without hurting real customer conversion.



Most merchants rely on "one per email" or "first order only." That's easy to bypass with aliases, temp mail, and new accounts. Most tools act after the order — so you still pay fees and do refunds.
One person, many accounts, same welcome or single-use code.
Flag then cancel or refund — no prevention at checkout.
OverlayIQ stops repeat discount use at checkout, so you keep margin and avoid the operational headache.
Set-it-and-forget-it. No manual review queues.
Device fingerprinting, fuzzy address matching, and IP intelligence so one person can't reuse first-time or single-use codes with a new email.
Via Shopify Functions we validate the moment a code is applied. If we detect a repeat user, we show a clear message — no order created, no fees, no refunds.
Prefer not to block? We can silently strip the discount or show "code expired" for that session. You keep the sale and protect the margin.
Monthly recovered margin report so you know your promo budget is working for real new customers.
First-time codes, referral programs, influencer offers.
One person, many accounts, same code. We block or downgrade at checkout so only true first-time customers get the offer.
Self-referrals, same household. We flag or block based on device, address, and behavior so referral rewards go to real new customers.
Codes shared or reused. We enforce at checkout so margin goes to real new customers and your promo budget stays efficient.
Estimated avoidable discount leakage at 3% of revenue.
| Monthly revenue | 3% leakage | Recovered |
|---|---|---|
| $500,000 | $15,000 | $15,000 |
| $1,000,000 | $30,000 | $30,000 |
| $2,000,000 | $60,000 | $60,000 |
We were leaking thousands a month on repeat first-time codes. OverlayIQ caught it at checkout so we never created the orders. Our margin report now shows exactly what we're saving.
— Head of Growth, DTC Brand
Common questions about blocking repeat discount abuse and recovering margin on Shopify.