The launch took place at 05:50 GMT.
"The satellite was deployed approximately 32 minutes after liftoff. Following stage separation, SpaceX successfully landed Falcon 9’s first stage on the "Of Course I Still Love You" drone ship in the Atlantic Ocean," SpaceX said in a press release.
Telstar 19V is designed to transmit broad-band signals in North and South America, as well as to provide Wi-Fi for air passengers over the North Atlantic.
This was the second launch of the new version of SpaceX's Block 5 rocket, which has much more capability to be reused compared to the previous version of the Falcon 9, the Block 4.