Free Download add-on Upgrade Coupons by Waindigo xenforo. Downlaod add-on xenforo Upgrade Coupons by Waindigo.
Add the ability for coupons to be created in the Admin Control Panel to be used when your members purchase account upgrades.
Email or post your coupon codes to members so they can use them as a discount when purchasing account upgrades, upto and including free upgrades.
Coupons currently only work for non-recurring upgrades. If using User Upgrades by Waindigo user upgrades with trial periods and tiered upgrades cannot have coupons applied to them.