The 10GB add-on now lasts for 14 days rather than just five.
Multiple add-ons can be purchased if you're travelling for longer or just need more data while you're away.
The add-on is available in conjunction with the Prepaid Epic Data, Prepaid Epic Value, Optus Prepaid Long Expiry, My Prepaid Ultra, Prepaid Ultra Plus, My Prepaid Ultimate and My Prepaid Long Expiry plans.
"By launching these new Add-Ons, we are continuing to deliver our prepaid customers great value. With the addition of 5 more destinations to selected prepaid plans we want customers travelling overseas to use their phone worry free," said Optus head of strategic projects Vidur Rattan.
"We understand the importance for our customers to be able to share their travel experiences with friends and family back home and by expanding our roaming Add-Ons, we are making it easy for them to stay connected."