Some coupon codes that give some discounts when you buy domains. I checked all of them myself just now. If you see any invalid/wrong code, let me know.

.com domains 30% off: gdr0802v
.com domains 30% off (new and renewals): gdr0802aq
new .coms 30% off: gb99 
.com 30% off: gdr0802wb 20%off: gdr0809ap

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