Per the Owners Manual, only the 350h has EV mode. I used this mode heavily in my ‘16 rx450h when I would enter slower city streets, so this is a bummer for me. It’s also makes the Energy Monitor useless, because though the hybrid battery charges itself from regular driving and regenerative braking, I have no EV mode to utilize it anymore. Very disappointing

 

I had the same thought as the EV mode was in our previous Rav4 and activate it while on neighborhood streets.

 

Guess its reserved for the RX450h+ PHEV.

 

I'm not surprised that there is not an "electric mode".
In our 2013 RX 450H, the gas motor would only shut off for a mile or so on the road, not much more then that.
In town, the motor shuts off at stop lights and stop signs.

 

If you have the Sport mode on, the EV mode will be disabled. If it is in normal mode, you should have some times when the engine will shut down like when you're at a stop light or driving around 25 mph.
My RX500 has a light on the dash labeled EV, and when that light is on solid green, the gas engine is not running.

So, if you want some EV I would suggest trying the normal or Eco modes and looking for the light.