If I turn off my watch S3 LTE, My iPhone battery drains in just a few hours.

[Aston441]

Sometimes I shut off my watch when I won't be using it for the day to conserve it's battery.

When I do this, my iPhone 6s+, which is usually fine with battery, sucks away it's battery, often draining completely in about 4 hours.

If the watch is on, this does not happen, even if the watch is sixty miles away as long as it's connected to my home wifi.

 

[44267547]

Sometimes I shut off my watch when I won't be using it for the day to conserve it's battery.

When I do this, my iPhone 6s+, which is usually fine with battery, sucks away it's battery, often draining completely in about 4 hours.

If the watch is on, this does not happen, even if the watch is sixty miles away as long as it's connected to my home wifi.

I would re-install your Apple Watch with your iPhone and set up as a new Apple Watch (Not restore), and see if that helps any battery drain issues.