This is a partial list of piano manufacturers. Most piano professionals have access to detailed information about these brands using a Piano Atlas to reference serial numbers, which are used to determine a piano's age using the year a piano was built. This information is often used in piano appraisals.

Aeolian (1868)
Albrecht, Charles (1779)
American Piano Company (1908)
A. Mittag (Berlin, 1800)
Astin Weight (Salt Lake City, 1959)
Alexander Herrmann (Germany, 1803-1993)
Babcock (Boston, 1810)
August Förster
Baldwin (1890)
Christian Baumann (1740-1816) Zweibrücken,Germany
Baumgardt Piano (1859) Stockholm, Sweden.
Baus Piano Company
Beale Piano (Sydney, 1893-1975)
Bechstein Pianoforte Fabrik AG (1853)
Behr Brothers Piano Company
Bell (Canada)
Bentley Piano Company
Beulhoff
Blüthner (1853)
Bohemia Piano
Bösendorfer (1828)
Brødrene Hals (Oslo, 1847-1925)
Boston (1991)
Brinsmead (London, 1835)
Broadwood and Sons (London, 1783)
C. Burlman & Co.
Cable and Sons (New York, 1852)
Cable, Hobart M. (Indiana, 1900)
The Cable Company (Chicago, 1880)
Challen (1804)
Chappell Pianos (London, 1811)
Charles R. Walter (Elkhart, Indiana)
Chas. S. Norris (Boston, circa 1930)
Chickering and Sons (Boston, 1823)
Chris Maene - Doutreligne (Ruiselede (BE), 1938)
Cunningham Piano Company (Philadelphia, 1891)
Currier Piano Co. (Marion, N. C., 1969)
Clementi
Danemann (London, 1893)
Decker Brothers (New York, 1862)
Eastman
Edmund (British Columbia)
Érard (Paris, 1777)
Estey Piano Corp (1869)
Estonia Piano Factory (1893)
EUTERPE
Fahr Albert (Zeitz, Germany 1887 - 1950)
Falcone (1984)
Fandrich & Sons
Fazioli (1978)
Feurich (1851)
J.C. Fischer (New York, 1840)
August Förster (1859)
Francis Connor (New York, 1871)
Gabler (New York, 1851)
Gaveau (Paris, 1847)
Generalmusic
Glenz (Josef) (Breslau)
Timothy Gilbert (Boston, 1827)
Goetzmann (New York)
Grotrian-Steinweg (1835)
Haines Brothers (New York, 1832)
Hallet, Davis & Co (Boston, 1835)
Hansmann
Hardman Peck (New York, 1842)
Heintzman & Co. (Toronto, 1866)
Hobart M. Cable (La Porte, Idiana 1900)
Hupfield (1880)
Ibach (1794)
Irmler (Leipzig/Poland)
J. Erbe Eisenach (Germany, 1881)
J. Strauss & Son (1925)
Kawai (1930)
Kemble (1911)
Kimball (Chicago, 1857)
Kirschner (New York)
Knabe (Baltimore, 1837)
Knight (1935)
Kohler & Campbell (New York, 1896)
Krakauer Bros (New York, 1869)
Kranich & Bach (1864)
Kurtzmann
Albert W. Ladd & Company (Boston, 1838)
Lesage (Quebec)
Lindeman & Sons (New York, 1836)
Leipziger Pianofortefabrik (1835)
Ludwig & Company (St. Louis, 1895)
Mammoth Piano (USA, 2010)
Mason & Hamlin (Boston, 1854)
Mason & Risch (Ontario)
Mathushek (New York, 1852, 1879) (New Haven, 1866)
Mendelssohn (Canada)
Moore and Moore (London)
Muir Wood & Co. (Edinburgh)
Murdoch, McKillop & Co (Edinburgh)
Joseph Newman (Baltimore 1829)
Newman & Bros. (Baltimore 1842)
Nordheimer (Canada)
Pape (Paris, 1817)
Obermann & Sohn
Overs (Sydney)
Perzina (1871)
Petrof (1864)
Petzold (Paris, 1806)
Pfeiffer (Stuttgart, 1862)
Prate (Canada)
Pirsson (New York, 1829)
Pleyel (Paris, 1807)
QRS (1900)
Quidoz (Quebec)
Rainer (Canada)
Reed & Sons (1842)
Rubenstein (2005)
Manuel Samaniego (died 1892, Madrid)
Samick (1958)
San Francisco Piano Co.
Sauter (1819)
Schiedmayer (1853)
Schimmel (Germany, 1885)
Scholze
Schultz & Sons (1948)
Schulze & Pollman
Schweighofer (1792 - 1938)
Seiler (1849)
Sherlock-Manning (Ontario)
Sherman Clay
Shomacker Philadelphia, 1840s-
Smith & Barnes
F.G. Smith (New York, 1866)
Sohmer & Co. (New York, 1872)
Steck (New York, 1857)
Steingraeber & Söhne (1852)
Steinway & Sons (New York and Hamburg, Germany, 1853)
Story & Clark (1884)
Streicher (1802)
Strich & Zeidler
Stuart and Sons
Suzuki Corporation
Thürmer (1834)
Uebel & Lechleiter (Heilbronn 1872-1987)
Weber (New York, 1852)
George Weber & son, John (Chicago, ? - 1917)
Weber (Canada)
Whelpdale, Maxwell & Codd (1876)
George Wilkinson (London, 1811)
Wilh. Steinberg (Germany, 1877)
Willis & Co. (Quebec)
Wornum (London, 1811)
Wurlitzer (1856)
Yamaha (1889)
Young Chang (1956)
Zimmermann (1884)