Hi @BWorley6 - Thanks for reaching out. It's exciting to hear you have a trip to the Tetons coming up!
For dispersed camping near Grand Teton National Park, you will most likely be looking in the Bridger-Teton National Forest. This area is not within the national park grounds, but there are places that are close enough for "commuting" if you are planning to go into the park each day.
The Jackson Ranger district of the Bridger-Teton National Forest has numerous options available. We suggest contacting the rangers before deciding on a location because accessibility is sometimes limited to four-wheel-drive or high clearance vehicles. That office can be contacted at 307-739-5400.
Hopefully this helps!
Dispersed camping is not allowed in Grand Tetons. You have to camp at approved backcountry campsites and need to have a permit. Check out the National Park webside: www.nps.gov/grte
We stayed two nights in Bridger-Teton NF this past September. I can't remember the exact road, but we headed east out of the NP and that takes you into the NF eventually (I'm sure you can find it on a map, but it was off 191 I think north of Jenny Lake). You can also take US-26/287 east and go south from there. Make sure to look at a map and memorize it while you have phone service (or better yet, download it or print off a topo map), because there are a lot of deceiving east-bound roads that dead-end. We were unprepared because the FC/FS campground we had planned to stay in was closed suddenly.
Once you get to the road, make sure you make it all the way off the national park grounds. There will be a lot of people set up along the way but don't be fooled. Maybe they just leave before the rangers do their rounds. We spent our two nights in what was apparently a daytime use area, past the other campers and came back to a warning left from a ranger. Fortunately our car wasn't there so he couldn't identify us to ticket us. This lead to packing up an icy tent at 4am instead of leaving for our 20 mile day, followed by sitting in line at the Jenny Lake campground for two hours and hoping for a campsite. We got the second to last spot and ended up getting off the trail just after dark, in a now hilarious serious of events that we still laugh about. That warning is still on my fridge.
Even from where we were it was about an hour drive into the park, so take that into account when planning.
There's a lot of beautiful wilderness back there. The stars that time of year were incredible. The sunset was on one side of the sky while the other side was littered with stars. We saw a huge bull moose amble along at the edge of the trees from our campsite. I'd almost say it's worth spending a couple days back there exploring if you've got the time.
Feel free to DM me if you have any more questions about the area! The Tetons are one of my favorite places on Earth and I'd be happy to share anything that might help 😊