1850 Atlas
| Name | What | Place | Pop | Other |
| Persia | T | Cattaraugus Co, NY | 1,953 | water by Cattaraugus creek |
| Persia | T | Boone Co, MO | ||
| Persifer | PO | Knox Co, IL | ||
| Persimon Creek | PO | Cherokee Co, NC | ||
| Perth | PT | Fulton Co, NY | 1,440 | water by Chucktenunda creek |
| Perth Amboy | City | Middlesex Co, NJ | 1,865 | water by Raritan bay & river |
| Peru | PT | Oxford Co, ME | 1,298 | water by Androscoggin river |
| Peru | PT | Bennington Co, VT | 567 | water by head waters of West river |
| Peru | PT | Berkshire Co, MA | 519 | |
| Peru | PT | Clinton Co, NY | 3,640 | water by Little Au Sable river & Lake Champlain |
| Peru | PT | Huron Co, OH | 1,632 | water by east branch of Huron river |
| Peru | T | Delaware Co, OH | ||
| Peru | PO | La Salle Co, IL | ||
| Peru | PV, CH | Miami Co, IN | seat of justice, water by Wabash river, Wabash & Erie canals | |
| Peru | PT | Pike Co, MO | ||
| Peru Mills | PO | Juniata Co, PA | ||
| Peruville | PV | Groton twp, Tompkins Co, NY | ||
| Petawla | PO | Randolph Co, GA | ||
| Peterborough | PV | Smithfield twp, Madison Co, NY | ||
| Peterborough | PT | Hillsborough Co, NH | 2,222 | water by branch of Contoocook river |
| Peters | T | Franklin Co, PA | 2,310 | water by west branch of Conecocheague creek |
| Peters | T | Washington Co, PA | 924 | water by Chartier's & Peter's creeks |
| Peters' Creek | PO | Bladen Co, NC | ||
| Peters' Creek | PO | Barren Co, KY | ||
| Petersburgh | PT | Rensselaer Co, NY | 1,908 | water by Little Hoosick creeks |
| Petersburgh | T | Huntingdon Co, PA | 264 | |
| Petersburgh | PB | Dinwiddie Co, VA | 14,010 | water by Appomattox river |
| Petersburgh | PV | Elbert Co, GA | water by Savannah & Broad rivers | |
| Petersburgh | PV | Lincoln Co, TN | ||
| Petersburgh | PV | Boone Co, KY | ||
| Petersburgh | PV | Springfield twp, Mahoning Co, OH | ||
| Petersburgh | PV | Pike Co, IN | seat of justice, water by White river | |
| Petersburgh | PV, CH | Menard Co, IL | seat of justice, water by Sangamon river | |
| Petersburgh | PO | La Vaca Co, TX | ||
| Petersburgh | PO | Cape May Co, NJ | ||
| Petersburgh Four Corners | PO | Petersburgh twp, Rensselaer Co, NY | ||
| Petersham | PT | Worcester Co, MA | 1,527 | water by Swift river |
| Peterstown | PV | Monroe Co, VA | water by Rich creek | |
| Petersville | PV | Northampton Co, PA | ||
| Peterville | PV | Frederick Co, MD | 2,351 | |
| Petit Jean | PT | Yell Co, AR | ||
| Pettis | T | Platte Co, MO | 2,954 | |
| Petra | PO | Saline Co, MO | ||
| Pettys | PO | Lawrence Co, IL | ||
| Pewaukee | PT | Waukesha Co, WI | ||
| Peytona | PO | Boone Co, VA | ||
| Peytonsburgh | PV | Pittsylvania Co, VA | ||
| Peyton's Creek | PO | Smith Co, TN | ||
| Peytonsville | PV | Williamson Co, TN | ||
| Pharisburgh | PV | Union Co, OH | ||
| Pharr's Mills | PO | Moore Co, NC | ||
| Pharsalia | PT | Chenango Co, NY | 1,185 | water by Geneganslette creek & Ostelic river |
| Pheasant Branch | PO | Dane Co, WI | ||
| Phelps | PT | Ontario Co, NY | 5,542 | water by Canandaigua outlet & Flint creek |
| Phelps | PT | Ashtabula Co, OH | water by Rock & Musquito creek | |
| Phelpstown | PT | Ingham Co, MI | 393 | |
| Phenix | PO | Kent Co, RI | (see Phoenix) | |
| Philadelphia | PT | Jefferson Co, NY | water by Indian river & tributaries | |
| Philadelphia | City | Philadelphia Co, PA | 121,376 | (census for city proper) |
| Philadelphia | PV | Neshoba Co, MS | seat of justice, water by Kentokey creek | |
| Philadelphia | PO | Darlington dist, SC | ||
| Philadelphia | PV | Monroe Co, TN | ||
| Philadelphia | PV | Hancock Co, IN | ||
| Philadelphia | PV | Van Buren Co, IA | water by Des Moines river & Lick creek | |
| Philadelphia | PO | Marion Co, MO | ||
| Philadelphus | PV | Robeson Co, NC | ||
| Philanthropy | PO | Reily twp, Butler Co, OH | ||
| Philipsburgh | PV | Rush twp, Centre Co, PA | water by Mushannon creek | |
| Philipsburgh | PV | Wells twp, Jefferson Co, OH | water by Ohio river | |
| Philipsport | PV | Mamakating twp, Sullivan Co, NY | on the Delaware & Hudson canal | |
| Philipstown | PV | White Co, IL | ||
| Philipsville | PV | Amity twp, Alleghany Co, NY | water by Genesee river | |
| Philipsville | PO | Weakley Co, TN | ||
| Phillippa | PO | Barbour Co, VA | ||
| Phillips | PT | Franklin Co, ME | 1,173 | water by Sandy river |
| Phillipsburgh | T | Beaver Co, PA | ||
| Phillipsburgh | PB | New Sewickly twp, Beaver Co, PA | water by Ohio river | |
| Phillips' Creek | PO | Alleghany Co, NY | ||
| Phillipston | PT | Worcester Co, MA | 809 | |
| Phillipstown | T | Putnam Co, NY | 5,063 | water by Hudson |
| Phillipsville | V | Granby twp, Oswego Co, NY | water by Oswego river | |
| Phillipsville | PO | Erie Co, PA | ||
| Philo | PO | Muskingum Co, OH | ||
| Philomath | PO | Union Co, IN | ||
| Philomath | PO | Oglethorpe Co, GA | ||
| Philomont | PV | Loudoun Co, VA | ||
| Philopolis | PO | Baltimore Co, MD | ||
| Phippsburgh | PT | Lincoln Co, ME | 1,805 | water by Kennebec river & Atlantic ocean |
| Phipp's Mills | PO | Venango Co, PA | ||
| Phoenix | not list | no county, RI | see Phenix | |
| Phoenix | PV | Schroeppel twp, Oswego Co, NY | 872 | water by Oswego river & canal |
| Phoenix | PO | Edgefield dist, SC | ||
| Phoenix | PO | Armstrong Co, PA | ||
| Phoenixville | PV | Schuylkill twp, Chester Co, PA | 2,670 | water by French creek at its confluence with Schuylkill river |
| Phoenixville | PO | Windham Co, CT |