—- copy and paste from CBA website —-

Credit cards
$300 cashback. Nicely played.
Apply for a new Low Rate Mastercard by 4 February 2018 and spend $1,000 within 90 days of activating your card to get $300 cashback.

Please note this offer is not available to customers who currently hold, or have held, any personal Low Rate, Low Rate Gold and/or Low Rate Business Credit Cards (personal liability) types in the 12 months prior to 1 November 2017.

Get $300 cashback with a new Low Rate credit card in 3 easy steps

Apply for a new Low Rate, Low Rate Gold or Low Rate Business credit card by 4 February 2018
Spend $1,000 on eligible purchases within 90 days of activating your new card.
That’s it. Your $300 cashback will be credited to your account within 60 days of spending $1,000.