For in-store purchase only and exclusively for its members, Costco offers the Samsung Galaxy S9 64GB Smartphone for T-Mobile bundled with a $100 Costco Cash Card and Tylt Power Essential Pack for $579.99. That's $100 under Costco's offer from March — which lacked the gift card and power pack — and the best deal we've seen for the recent Galaxy phone on the T-Mobile network. (The phone itself on T-Mobile otherwise goes for around $720.)

Meanwhile, Costco members can also avail of the Samsung Galaxy S9+ 64GB Smartphone for T-Mobile bundled with a $100 Costco Cash Card and Tylt Power Essential Pack for $699.99. Again, that's $100 under Costco's deal from March of just the phone, and it's a low now by $140 (before factoring in the Costco Cash). Both deals end June 17.

The Costco Cash must be redeemed online; it may take up to 90 days for you to receive it.