See the following example for a OW search NYC-HKG offering a 7.5% discount:
Discounted Search (using code ZTG7960642):
Please post in the comments if coupon / offer code ZTG7960642 does not work for your location / dates. As you can see from the slickdeals thread, there is not much information available about this code, just that the code appears to be intended for Realtor.org convention participants.
Realtor.org also highlights a code for Delta flights, but it appears to be limited to certain locations/dates by the system.
“Delta Air Lines is pleased to offer special discounted airfares (5-10% discount) for the Conference & Expo!
HT: CSIG1001 @ SLICKDEALS
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