Chase referral links can be found for all cards at this Chase page. On new Chase cards, the link sometimes will not appear there for some number of months. Reddit user og_mclovin suggests that this can sometimes be found in the Chase app, even before it shows up online.
Within the Chase app, tap on the card you are looking for, then find Refer-a-Friend link. For personal cards: Rewards and Benefits > See reward details & redeem > Earn > Refer. For business cards: Account Services > Refer Businesses.
Not all cards will show the referral option there, but on the cards that do show it you may find a working referral link immediately, even before it populates on the website.
