Municipalities in Pennsylvania's 12th Congressional District:

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Part of Allegheny County consisting of the Township of East Deer Ward 2, Forward Ward 3 and the Borough of Tarentum.

Part of Armstrong County consisting of the Townships of Bethel, Burrell, Gilpin, Kiskiminetas, Manor, North Buffalo - East, Parks, Plumcreek, South Bend and South Buffalo District Eastern, and the Boroughs of Apollo, Elderton, Ford City, Ford Cliff, Freeport, Kittanning, Leechburg, Manorville and North Apollo.

Part of Cambria County consisting of the City of Johnstown; the Townships of Adams, Barr, Blacklick, Cambria, Conemaugh, Cresson, Croyle, East Carroll, East Taylor, Jackson, Lower Yoder, Middle Taylor, Munster, Portage, Richland, Stonycreek, Summerhill, Upper Yoder, Washington, West Carroll and West Taylor; and the Boroughs of Brownstown, Carrolltown, Cassandra, Cresson, Daisytown, Dale, East Conemaugh, Ebensburg, Ehrenfeld, Ferndale, Franklin, Geistown, Lilly, Lorain, Nanty Glo, Portage, Sankertown, Scalp Level, South Fork, Southmont, Susquehanna - North, Summerhill, Vintondale, Westmont and Wilmore.

Part of Fayette County consisting of the Cities of Connellsville Ward Ward 1, 2, 3 and 6, and Uniontown; the Townships of Brownsville, Bullskin, Dunbar Districts 2, 3 and 4, Franklin, Georges Districts 3 and 4, German, Jefferson, Lower Tyrone, Luzerne, Menallen, North Union Districts 1, 2, 4 and 5, Perry, Redstone, Saltlick, South Union Districts 1 and 2, Springhill District 2, Upper Tyrone and Washington; and the Boroughs of Belle Vernon, Brownsville, Dawson, Dunbar, Everson, Fayette City, Masontown, Newell, Perryopolis, Point Marion and Vanderbilt.

All of Greene County.

Part of Indiana County consisting of the Townships of Cherryhill, Pine and White Districts 1 and 2, and the Boroughs of Clymer and Indiana Districts 2 and 3.

Part of Somerset County consisting of the Townships of Conemaugh, Jefferson, Jenner, Lincoln, Middlecreek, Paint and Quemahoning, and the Boroughs of Benson, Boswell, Hooversville, Jennerstown, Paint, Seven Springs, Stoystown and Windber.

Part of Washington County consisting of the Cities of Monongahela and Washington and the Townships of Canton, Carroll Districts 2, 3 and 5, Chartiers Districts 3, 5, 6 and 7, East Bethlehem, Fallowfield Districts 1, 2 and 4, North Bethlehem, North Strabane Districts 2, and 3 (only blocks 3016, 3017, 4004, 4005, 4006, 4007, 4011, 4012, 4013 and 4015 of tract 745100), Somerset, South Strabane Districts 2, 4 and 5, Union, West Bethlehem; and West Pike Run and the Boroughs of Allenport, Beallsville, Bentleyville, California, Canonsburg Wards 2 and 3 (Division 1), Centerville, Charleroi Districts 1, 3 and 4, Coal Center, Cokeburg, Deemston, Donora, Dunlevy, East Washington District 2, Elco, Ellsworth, Finleyville, Houston, Long Branch, Marianna, New Eagle, North Charleroi, Roscoe, Speers, Stockdale, Twilight and West Brownsville.

And part of Westmoreland County consisting of the Cities of Arnold, Latrobe, Lower Burrell, Monessen and New Kensington and the Townships of Allegheny, Bell, Derry districts Alters, Brandenville, Cokeville, Cooperstown, Kingston, Loyalhanna, Millwood, New Derry, Peanut, Saxman, Scalp Level, and Simpsons, Derry, East Huntingdon District Bessemer, Fairfield, Hempfield Districts Bovard, Hannastown and Luxor, Loyalhanna, Mount Pleasant Districts Bridgeport, Duncan, Heccla, Laurel Run, Mammoth, Spring Garden, United and Westmoreland, Rostraver, Salem Districts Hugus and Mechlings, Sewickley Districts East Herminie, Lowber, Rillton, Sewickley and West Herminie, South Huntingdon Districts Jacobs Creek, Mineral, Port Royal, Wayne, Wyano and Yukon, St. Clair, Unity Districts Crabtree, Dorothy, Lloydsville, Pleasant Unity and Mutual , Upper Burrell and Washington Districts North Washington and Paulton; and the Boroughs of Avonmore, Bolivar, Derry, East Vandergrift, Hyde Park, Mount Pleasant, New Alexandria, New Florence, North Belle Vernon, Oklahoma, Scottdale, Seward, Smithton, Vandergrift, West Leechburg and West Newton.