Incorporated 1895, acquired 1902 by Pittsburgh Railways.
Allegheny Traction Co. - incorporated 1889, in 1894 acquired Millvale Etna & Sharpsburg Passenger Railway (incorporated 1892, opened 1894), and Millvale Etna & Sharpsburg Street Railway (incorporated 1892). Also leased Transverse Passenger Railway Co. from Citizens Traction Co. Leased 1896 by Fort Pitt Traction Co., lease assumed shortly after by Consolidated Traction Co.
Ardmore Street Railway - incorporated 1907, opened 1908. Leased 1908 by Consolidated Traction Co.
Central Passenger Railway Co. - incorporated 1889. Leased 1894 by Central Traction Co., acquired 1896 by Consolidated Traction Co.
Central Traction Co. - incorporated 1888, opened 1890. Leased 1896 by Consolidated Traction Co.
Citizens Traction Co. - incorporated 1887, leasing Citizens Passenger Railway Co. (incorporated 1859), and Transverse Passenger Railway Co. In 1893 leased Pennsylvania Street Passenger Railway (incorporated 1892, opened 1893). Leased 1895 by Fort Pitt Traction Co., lease assumed in 1996 by Consolidated Traction Co.
Aspinwall Street Railway - incorporated 1892, opened 1894. Leased 1895 by Citizens Traction Co.
Bellefield Street Railway - incorporated 1892, opened 1894. Acquired 1897 by Duquesne Traction Co.
Duquesne Traction Co. - incorporated 1890, leasing Duquesne Street Railway (incorporated 1890), and the following eight companies which were merged into Duquesne Street Railway in 1892. Boyd Street Railway (incorporated 1890), Craig Street Passenger Railway (incorporated 1889), East End Street Railway (incorporated 1889), Grant Street Railway (incorporated 1890), Highland Street Railway (incorporated 1890), Howe Street Railway (incorporated 1889), Larimer Street Railway (incorporated 1889), Wilkinsburg & East Liberty Railway (incorporated 1890). In 1891, Duquesne Traction Co. leased Market Street Railway (incorporated 1890), and People's Street Railway (incorporated 1890, opened 1891). Leased 1896 by Fort Pitt Traction Co., lease assumed shortly after by Consolidated Traction Co.
Fort Pitt Traction Co. - incorporated 1895, acquiring Fort Pitt Street Passenger Railway, Gross Street Railway, Highland Park Passenger Railway, Highland Passenger Railway, and Negley Street Railway. From 1895 to 1896 leased Allegheny Traction Co., Citizens Traction Co., and Duquesne Traction Co. (three companies listed above). Leases of all three companies assumed in 1896 by Consolidated Traction Co.
Monongahela Street Railway Co. - incorporated 1898, acquiring Braddock & Duquesne Street Railway (opened 1908), Braddock & Homestead Street Railway, and Homestead & Highlands Street Railway (incorporated 1892, opened 1895). In 1901, acquired Wilkinsburg & East Pittsburgh Street Railway (incorporated 1899, acquiring Braddock Electric Passenger Railway Co. which was incorporated 1890). In 1901, also acquired Wilkinsburg & Verona Street Railway. Leased 1902 by Consolidated Traction Co.
Morningside Electric Street Railway - incorporated 1904, leased 1905 by Consolidated Traction Co.
Pittsburgh Traction Co. - incorporated 1887, acquiring Central Traction Co. In 1887, leased Pittsburgh Oakland & East Liberty Railway Passenger Railway (incorporated 1859), and in 1893 leased Bloomfield Street Railway (incorporated 1892). Leased 1896 by Consolidated Traction Co.
Suburban Rapid Transit Street Railway - incorporated 1886, opened 1888, in 1899 acquired South Twenty-Second Street Railway Co. (incorporated 1886). Leased 1902 by Consolidated Traction Co.
Incorporated 1896, acquired 1902 by Pittsburgh Railways.
Allegheny Bellevue & Perrysville Railway - incorporated 1905, acquiring Bellevue & Perrysville Street Railway, and Howard & East Street Railway Co. Leased 1905 by United Traction Co.
Ben Avon & Emsworth Street Railway - incorporated 1903, leased 1903 by by United Traction Co.
East McKeesport Street Railway - incorporated 1899, leased 1902 by by United Traction Co.
Federal Street & Pleasant Valley Railway - incorporated 1868, opened 1869. In 1889 acquired Observatory Hill Railroad Co., and People's Park Passenger Railroad Co. In 1892 acquired Allegheny & Bellevue Railway Co., Allegheny Street Railway Co., Perry Street Railway Co., and Troy Hill Railway Co. Leased 1896 by North Side Traction Co. (incorporated 1896), lease assumed shortly after by United Traction Co.
Pittsburgh Allegheny & Manchester Traction Co. - incorporated 1889, acquired in 1891 Pittsburgh Allegheny & Manchester Passenger Railway (incorporated and opened 1859), Pittsburgh Union Passenger Railway (incorporated 1879, opened 1881), and Union Passenger Railway Co. (incorporated 1878, opened 1881, merged into Pittsburgh Union Passenger Railway in 1881). Leased 1897 by by United Traction Co.
Pittsburgh & Birmingham Traction Co. - incorporated 1889. In 1889 leased Pittsburgh & Birmingham Passenger Railway (incorporated 1859), South Side Passenger Railway (incorporated 1874, operated by Pittsburgh & Birmingham Passenger Railway until 1889). In 1894 leased Birmingham Knoxville & Allentown Traction Co., in 1896 leased Brownville Avenue Street Railway (incorporated 1896), and leased West Liberty Street Railway Co. Leased 1902 by by United Traction Co.
Pittsburgh & Charleroi Street Railway - incorporated 1902, opened 1903. Acquired 1902 by by United Traction Co.
Second Avenue Traction Co. - incorporated 1894, leasing Second Avenue Passenger Railway (incorporated 1881). Second Avenue Passenger Railway subsequently had acquired Hazlewood Homestead & Braddock Passenger Street Railway, Braddock & Turtle Creek Passenger Street Railway (incorporated 1885, opened 1891), and Greenfield Avenue Railway Co. (incorporated 1890, opened 1892). Second Avenue Traction Co. also leased Glenwood & Dravosburg Passenger Railway (incorporated 1894 through merger of Dravosburg Passenger Railway and Pittsburgh & Homestead Passenger Railway), and McKeesport & Reynoldtown Passenger Railway (incorporated 1889). In 1895 assumed ownership of McKeesport & Reynoldtown Passenger Railway. Acquired 1897 by by United Traction Co.
Incorporated 1900 as Southern Traction Co., renamed 1901 to Pittsburgh Railways Co. In 1902, assumed control of Consolidated Traction Co. and United Traction Co., operating under contract. Also acquired the following street railway companies.
Allegheny Evergreen & Millvale Street Railway - incorporated 1904, acquired 1906 by Pittsburgh Railways Co.
Allenport & Roscoe Electric Street Railway - incorporated 1903, acquired 1903 by Pittsburgh Railways Co.
Ambridge Dixmonte & Elmsworth Street Railway - acquired by Pittsburgh Railways Co.
Bates Street Railway - incorporated 1902, acquired 1902 by Pittsburgh Railways Co.
Bon Air Street Railway - incorporated 1905, acquired 1905 by Pittsburgh Railways Co.
Brereton Avenue Street Railway - incorporated 1902, acquired 1902 by Pittsburgh Railways Co.
Carrick & Baldwin Street Railway - incorporated 1908, acquired 1908 by Pittsburgh Railways Co.
Cedar Avenue Street Railway - incorporated 1901, acquired 1901 by Pittsburgh Railways Co.
Charleroi & West Side Street Railway - incorporated 1899, acquiring Charleroi Bellvernon & Fayette Street Railway (incorporated 1897, opened 1898). Sold 1902 to Pittsburgh & Charleroi Street Railway, leased 1902 to Pittsburgh Railways.
Crafton & Chartiers Valley Traction Co. Acquired 1900 by Southern Traction Co.
McKees Rocks & Allegheny Street Railway Acquired by Pittsburgh Railways Co.
McKees Rocks & Ingram Street Railway Acquired 1900 by Southern Traction Co.
McKees Rocks & Neville Island Street Railway Acquired 1900 by Southern Traction Co.
Mount Washington Street Railway - incorporated 1903, opened 1904. Leased 1903 by Pittsburgh Railways Co.
New Homestead Street Railway Co. - incorporated 1900, acquired 1900 by Southern Traction Co.
Pittsburgh & Castle Shannon Railroad - incorporated 1871 as steam railroad, leased 1905 by Pittsburgh Railways Co.
Pittsburgh Banksville & Mount Lebanon Street Railway Co. Acquired 1900 by Southern Traction Co.
Pittsburgh Monongahela & Washington Railway Co. - incorporated 1907 as Monongahela & Carroll Street Railway Co., acquired by Pittsburgh Railways Co.
Pittsburgh Southern Street Railway - incorporated 1900, acquired 1900 by Southern Traction Co.
Rosslyn Street Railway - acquired 1903 by Pittsburgh Railways Co.
Superior Avenue & Shady Street Railway - incorporated 1901, acquired 1901 by Pittsburgh Railways Co.
Tustin Street Railway - incorporated 1899, opened 1900 as connection between Consolidated Traction Co. and United Traction Co. Acquired 1902 by Pittsburgh Railways Co.
Virginia Avenue Street Railway Co. Acquired 1900 by Southern Traction Co.
Washington & Canonsburg Railway Co. - incorporated 1902 as merger of Canonsburg Street Railway Co., and Washington Electric Street Railway (incorporated 1889, opened 1891), which in 1895 acquired Washington & Tylerdale Street Railway. In 1907 leased Pittsburgh Canonsburg & Washington Railway (incorporated 1907). Acquired 1909 by Pittsburgh Railways Co.
Washington & Clayville Street Railway - incorporated 1905, acquired 1905 by Pittsburgh Railways Co.
West End Traction Co. - incorporated 1897. In 1898, acquired West End Mount Washington & Banksville Railway, and Pittsburgh & West End Passenger Railway. Pittsburgh & West End Passenger Railway was incorporated and opened 1879, and in 1894 acquired Pittsburgh Neville Island & Coraopolis Electric Railway (incorporated 1893), and in 1895 acquired Pittsburgh Crafton & Mansfield Street Railway (incorporated 1893). Acquired 1900 by Southern Traction Co.
West Liberty & Suburban Street Railway - incorporated 1905, acquired 1905 by Pittsburgh Railways Co.
West Shore Electric Street Railway - incorporated 1905, acquired 1905 by Pittsburgh Railways Co.
Millvale Passenger Railway Co. - incorporated 1889, ceased operations 1890's.
Forty-Third Street & Bloomfield Passenger Railway - incorporated 1889, ceased operations 1890's.
Highland Grove Traction Co. - incorporated 1900. Ceased operations.
Homestead & Mifflin Street Railway - incorporated 1901, opened 1902. Ceased operations.
Mount Troy & Reserve Township Traction Street Railway - incorporated 1892, opened 1900. Ceased operations shortly after.
Schenley Park & Highlands Railway - incorporated 1891, ceased operations 1890's.
Troy Hill Inclined Plane & Bridge Co. - incorporated 1887 as Troy Hill Inclined Plane Co., in 1888 acquired Thirtieth Street Bridge Co. and renamed Troy Hill Inclined Plane & Bridge Co. Ceased operations 1898.
Wilkinsburg Street Railway - incorporated 1890, ceased operations 1890's.