As of 1884 (interpreted from Form 76), the Pennsylvania Railroad -- which did not include "Lines West of Pittsburgh" -- was organized into Grand Divisions, Divisions, and Railroads. Railroads represented in bold are included in the listings but are believed to be independent railroads (many are confirmed so).
| Grand Division | Division | Railroad |
| United Railroads of New Jersey Division | New York Division | |
| New Jersey Central Division P. & R. R.R. | ||
| New York & Long Branch R.R. | ||
| Amboy Division | ||
| Belvidere Delaware R.R. (Trenton Yard) | ||
| Belvidere Delaware R.R. | ||
| West Jersey Railroad | ||
| Camden & Atlantic Railroad | ||
| Pennsylvania Railroad Division | Philadelphia Division | Schuylkill River Branch |
| Junction R.R. | ||
| Delawre Extension | ||
| Frederick Division | ||
| Middle Division | ||
| Lewistown Division | Mifflin & Centre County R.R. | |
| Sunbury & Lewistown R.W. | ||
| Huntingdon & Broad Top Mountain R.R. | ||
| Bedford Division | Bedford & Bridgeport R.R. | |
| Tyrone Division | Lewisburg & Tyrone R.R. | |
| Tyrone Branch | ||
| Bald Eagle Valley R.R. | ||
| Tyrone & Clearfield R.W. | ||
| Altoona Division | ||
| Pittsburgh Division | ||
| West Pennsylvania Division | Indiana Branch | |
| West Pennsylvania R.R. | ||
| Monongahela Division | P. V. & C. R.W. | |
| Philadelphia, Wilmington & Baltimore R.R. | Maryland Division | Washington Avenue |
| Alexandria & Fredericksburg R.W. | ||
| Alexandria & Washington R.R. | ||
| Baltimore & Potomac R.R. | ||
| Maryland Division | ||
| Central Division | ||
| Delaware Division | ||
| Baltimore & Delaware Bay R.R. | ||
| Northern Central Railway | Baltimore Division | |
| Susquehanna Division | ||
| Shamokin Division | S. V. & P. R.R. | |
| Sunbury Division | S., H. & W. R.W. | |
| Elmira Division | ||
| Chemung Division | ||
| Canandaigua Division | ||
| Philadelphia & Erie R.R. Division | North and West Branch R.W. | |
| Eastern Division | ||
| Middle Division | ||
| Western Division | ||
