Launching yesterday in North America, the real-money auction houses are due to arrive in Europe on Friday, June 15, according to an in-game notification.
The auction house allows users to sell and bid on in-game items using actual money instead of the game's currency.
Users who sell items for cash will be charged a 15% transaction fee, but only when items successfully sell.
A separate auction house, which uses in-game gold as currency, will be available as an alternative.
The real-money auction house was originally due to arrive on May 22, but was pushed back as Blizzard focused on solving server issues that have plagued the game since its release.
An update for the game was also recently announced that will optimise it for use on the new MacBook Pro line with Retina displays.
Diablo 3 launched earlier this month. The game is free to users who sign up for the World of Warcraft annual pass, a yearly subscription to the popular MMO.
A Starter Edition of the game has also been confirmed, offering a limited introduction to Diablo 3 with content similar to its private beta.
Watch the Diablo 3 launch trailer below: