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 |
|---|---|---|
| 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 | |
| Atlanta | Georgia | Atlanta |
| JESSE CRAWFORD | Montana | Billings |
| Binghamton Theatre Organ Society, Inc. | New York | Binghamton |
| Alabama | Alabama | Birmingham |
| Piedmont | North Carolina | Burlington |
| Free State | Maryland | Catonsville |
| Cedar Rapids | Iowa | Cedar Rapids |
| Cumberland Valley | Pennsylvania | Chambersburg |
| Chicago Area | Illinois | Chicago |
| Chicagoland | Illinois | Chicago |
| Ohio Valley | Ohio | Cincinnati |
| Western Reserve | Ohio | Cleveland |
| Pikes Peak | Colorado | Colorado Springs |
| North Texas | Texas | Dallas / Ft. Worth |
| Rocky Mountain | Colorado | Denver |
| Motor City | Michigan | Detroit |
| Detroit Theatre Organ Society (affiliate) | Michigan | Detroit |
| Red River Theatre Organ Society | North Dakota | Fargo |
| Orange County | California | Fullerton |
| Houston | Texas | Houston |
| Central Indiana | Indiana | Indianapolis |
| Garden State | New Jersey | Jersey City |
| Joliet Area | Illinois | Joliet |
| Kansas City | Missouri | Kansas City |
| Kingston | Canada | Kingston |
| Lansing Theatre Organ, Inc. (affiliate) | Michigan | Lansing |
| Bluegrass | Kentucky | Lexington |
| London and South of England | England, General | London |
| Los Angeles | California | Los Angeles |
| Carolina Theatre Organ Society | North Carolina | Matthews |
| Dairyland | Wisconsin | Milwaukee |
| Land O' Lakes | Minnesota | Minneapolis / St. Paul |
| New York | New York | New York City |
| Pine Tree | Maine | Old Orchard Beach |
| River City | Nebraska | Omaha |
| Valley of the Sun | Arizona | Phoenix |
| Pittsburgh Area Theatre Organ Society (Affiliate) | Pennsylvania | Pittsburgh |
| Columbia River | Oregon | Portland |
| Old Dominion | Virginia | Richmond |
| Rochester Theatre Organ Society (affiliate) | New York | Rochester |
| Sierra | California | Sacramento |
| Great Lakes Bay | Michigan | Saginaw |
| GREAT SALT LAKE | Utah | Salt Lake City |
| San Diego | California | San Diego |
| NorCal | California | San Francisco |
| Santa Barbara | California | Santa Barbara |
| Manasota | Florida | Sarasota |
| Hudson Mohawk | New York | Schenectady |
| Puget Sound | Washington | Seattle |
| Spokane First Nazarene | Washington | Spokane |
| Saint Louis | Missouri | St. Loius |
| NORTHERN MICHIGAN | Michigan | Traverse City |
| Sooner State | Oklahoma | Tulsa |
| Dickinson Theatre Organ Society | Delaware | Wilmington |
| Susquehanna Valley | Pennsylvania | York |