The Maine Island Trail is built on a foundation of partnerships. In particular, Trail site owners make the Maine Island Trail possible. MITA is grateful to the many private landowners, nonprofit organizations, and federal, state and municipal agencies that have chosen to include their properties on the Maine Island Trail. MITA recognizes the generosity of the following public and nonprofit site owners:
- Acadia National Park
- American Lighthouse Foundation
- Appalachian Mountain Club
- Blue Hill Heritage Trust
- Boothbay Region Land Trust
- Bowdoin College
- Chebeague & Cumberland Land Trust
- Chewonki Foundation
- City of Bath
- City of Portland
- Cuckolds Fog Signal & Light Station Council
- Coastal Mountains Land Trust
- Coastal Rivers Conservation Trust
- Downeast Coastal Conservancy
- Freeport Conservation Trust
- Freeport Historical Society
- Friends of Nature
- Friends of Seguin Island
- Georges River Land Trust
- Harpswell Heritage Land Trust
- Hurricane Island Foundation
- Hurricane Island Outward Bound
- Island Heritage Trust
- Kennebec Estuary Land Trust
- Kennebunkport Conservation Trust
- Kennebunk Land Trust
- Maine Audubon
- Maine Bureau of Parks & Lands
- Maine Coast Heritage Trust
- Maine Coastal Islands National Wildlife Refuge
- Maine Department of Inland Fisheries & Wildlife
- Maine Sport Outfitters
- Midcoast Conservancy
- National Audubon Society
- North Haven Conservation Partners
- Oceanside Conservation Trust
- Portland Trails
- Rachel Carson National Wildlife Refuge
- Rippleffect
- Royal River Conservation Trust
- Town of Bar Harbor
- Town of Brunswick
- Town of Camden
- Town of Cape Elizabeth
- Town of Harpswell
- Town of Kittery
- Town of Lamoine
- Town of Lubec
- Town of Machiasport
- Town of North Haven
- Town of St George
- Town of Surry
- Town of Swans Island
- Town of Tremont
- Wells Reserve
- Wood Island Life Saving Station Association