The 11 counties most often viewed as part of the Southern Tier include:
And the 3 Southern Tier West counties less-often included:
County Planning Agencies
- Allegany County Development
- Broome County Department of Planning & Economic Development
- Cattaraugus County Department of Economic Development, Planning & Tourism
- Chautauqua County Department of Planning & Economic Development
- Chemung County Planning Department
- Chenango County Planning & Development
- Cortland County Planning Department
- Delaware County Planning Department – View test data for Delaware County NY
- Otsego County Planning Department
- Schoharie County Office of Community Development
- Schuyler County Planning Department
- Steuben County Planning Department
- Tioga County Department of Economic Development & Planning
- Tompkins County Planning Department