Local Chapters of ATOS are the organizations that really do all the work of preserving and presenting Theatre Organ to the public. Please lookup the Chapters in your area and get involved!
| Chapter | State/Prov. | City |
|---|---|---|
| Susquehanna Valley | Pennsylvania | York |
| Dickinson Theatre Organ Society | Delaware | Wilmington |
| Sooner State | Oklahoma | Tulsa |
| NORTHERN MICHIGAN | Michigan | Traverse City |
| Saint Louis | Missouri | St. Loius |
| Spokane First Nazarene | Washington | Spokane |
| Puget Sound | Washington | Seattle |
| Hudson Mohawk | New York | Schenectady |
| Manasota | Florida | Sarasota |
| Santa Barbara | California | Santa Barbara |
| NorCal | California | San Francisco |
| San Diego | California | San Diego |
| GREAT SALT LAKE | Utah | Salt Lake City |
| Great Lakes Bay | Michigan | Saginaw |
| Sierra | California | Sacramento |
| Rochester Theatre Organ Society (affiliate) | New York | Rochester |
| Old Dominion | Virginia | Richmond |
| Columbia River | Oregon | Portland |
| Pittsburgh Area Theatre Organ Society (Affiliate) | Pennsylvania | Pittsburgh |
| Valley of the Sun | Arizona | Phoenix |
| River City | Nebraska | Omaha |
| Pine Tree | Maine | Old Orchard Beach |
| New York | New York | New York City |
| Land O' Lakes | Minnesota | Minneapolis / St. Paul |
| Dairyland | Wisconsin | Milwaukee |
| Carolina Theatre Organ Society | North Carolina | Matthews |
| Los Angeles | California | Los Angeles |
| London and South of England | England, General | London |
| Bluegrass | Kentucky | Lexington |
| Lansing Theatre Organ, Inc. (affiliate) | Michigan | Lansing |
| Kingston | Canada | Kingston |
| Kansas City | Missouri | Kansas City |
| Joliet Area | Illinois | Joliet |
| Garden State | New Jersey | Jersey City |
| Central Indiana | Indiana | Indianapolis |
| Houston | Texas | Houston |
| Orange County | California | Fullerton |
| Red River Theatre Organ Society | North Dakota | Fargo |
| Motor City | Michigan | Detroit |
| Detroit Theatre Organ Society (affiliate) | Michigan | Detroit |
| Rocky Mountain | Colorado | Denver |
| North Texas | Texas | Dallas / Ft. Worth |
| Pikes Peak | Colorado | Colorado Springs |
| Western Reserve | Ohio | Cleveland |
| Ohio Valley | Ohio | Cincinnati |
| Chicago Area | Illinois | Chicago |
| Chicagoland | Illinois | Chicago |
| Cumberland Valley | Pennsylvania | Chambersburg |
| Cedar Rapids | Iowa | Cedar Rapids |
| Free State | Maryland | Catonsville |
| Piedmont | North Carolina | Burlington |
| Alabama | Alabama | Birmingham |
| Binghamton Theatre Organ Society, Inc. | New York | Binghamton |
| JESSE CRAWFORD | Montana | Billings |
| Atlanta | Georgia | Atlanta |
| Connecticut Valley | Connecticut | |
| Central Florida | Florida | |
| South Florida | Florida | |
| EASTERN MASSACHUSETTES | Massachusetts | |
| MAGNOLIA | Mississippi | |
| Delaware Valley - Eastern Pennsylvania | Pennsylvania | |
| LA CROSSE SCENIC BLUFFS | Wisconsin | |
| Packerland | Wisconsin | |
| Australia Felix | Australia-Wide | |
| Cinema Organ Society (affiliate) | United Kingdom | |
| Southern Jersey | New Jersey |