What to say about Phillips? In many ways, it’s the “go to” backcountry sled zone around Jackson Hole. It’s close and it’s good. The only problem is that it’s a bit of a pain in the ass to get your sled to because of the trailer ban on Teton Pass in the winter.
However, if you have a truck, a friend with one, or like ignoring trailer bans, in many ways Phillips is the place to go. From the parking lot halfway up the pass on the left, ride on the Idaho-bound side of the road until you reach the Phillips Canyon Road. From there, follow the road into the back bowls.
The snowmobiling is fairly straightforward (and really good, too). I’d suggest exploring the different bowls before lining up some shuttles. There’s a lot of terrain so don’t get sucked into the first thing you see.
Also, it’s worth noting that this zone is extremely close to Teton Pass (Ski Area) where there there are lots, and lots, of backcountry hikers. Inevitably, backcountry hikers/skiers trickle into some of the zones you can sled to. All I can say is be respectful of one another, and maybe if people are hiking a zone, you should find another to sled in.