Google Pixel 2: You are paying full price for the phone over 24 months, and you will see the $300 promo applied to your account as a small credit each month starting in 1-2 billing cycles. This ends when the balance is fully paid, or if you cancel or transfer your line. There is no trade-in required.
S9 Pre-order: Up to $929.99 device payment purchase, port-in & new line activation required. Up to $350 trade-in/promo credit applied to account over 24 mos.; promo credit ends when balance paid or line terminated/transferred to another plan; 0% APR. Trade-in must be in good working & cosmetic condition.