1850 Atlas
| Name | What | Place | Pop | Other |
| Pin Oak | PO | De Buque Co, IA | ||
| Pingree Grove | not listed | Kane Co, IL | ||
| Pink | PT | Wayne Co, PA | ||
| Pink Hill | PO | Marshall Co, MS | ||
| Pink Hill | PO | Lenoir Co, NC | ||
| Pinkham's Grant | T | Coos Co, NH | ||
| Pinkney | see Pinckney | |||
| Pinkney | PO | Lewis Co, NY | ||
| Pinkney | T | Calhoun Co, MI | ||
| Pinnellville | PO | Jones Co, MS | ||
| Pintlala | PO | Montgomery Co, AL | water by Pintlala river | |
| Pintlee's Corners | PO | Ottawa Co, MI | ||
| Piny | PO | Clarion Co, PA | ||
| Piny Green | PO | Onslow Co, NC | ||
| Pioneer | PO | Greene Co, IL | ||
| Pioneer | PO | Williams Co, OH | ||
| Pioneer Grove | PO | Cedar Co, WI | ||
| Pioneer Mills | PO | Cabarras Co, NC | ||
| Pipe Creek | PO | Madison Co, IN | ||
| Pipe Stem | PO | Mercer Co, VA | ||
| Pipe Stone | PO | Berrien Co, MI | ||
| Pipersville | PO | Bucks Co, PA | ||
| Piqua | PV | Miami Co, OH | 3,277 | water by Miami river & canal |
| Piquea | PO | Lancaster Co, PA | ||
| Piscataway | T | Middlesex Co, NJ | 2,975 | water by Amherst and Cedar brooks |
| Piscola | PO | Lowndes Co, GA | ||
| Pisgah | PO | Butler Co, OH | ||
| Pisgah | PO | Union Co, IA | ||
| Pishon's Ferry | PO | Kennebec Co, ME | ||
| Pistol Creek | PO | Wilkes Co, GA | ||
| Pitcairn | PT | St Lawrence Co, NY | 503 | water by south west branch of Oswegatchie river |
| Pitcher | PT | Chenango Co, NY | 1,503 | water by Ostelic river |
| Pitcher Springs | PV | Pitcher twp, Chenango Co, NY | near village are 3 sulphur springs of some celebrity | |
| Pitch Landing | PV | Hertford Co, NC | water by Piney creek | |
| Pitman | PO | Schuylkill Co, PA | ||
| Pitt | T | Alleghany Co, PA | 2,033 | water by Alleghany & Monongahela rivers |
| Pitt | T | Crawford Co, PA | ||
| Pitts' Grove | PT | Salem Co, NJ | 1,151 | water by tributaries of Maurice run |
| Pitts' Point | PO | Bullitt Co, KY | ||
| Pittsborough | PV, CH | Chatham Co, NC | seat of justice, water by Robinson creek | |
| Pittsborough | PO | Hendricks Co, IN | ||
| Pittsburgh | City | Alleghany Co, PA | 46,601 | at head waters of Ohio river |
| Pittsburgh | PT | Coos Co, NH | 425 | water by head waters of Connecticut river |
| Pittsburgh | PV | Carroll Co, IN | 336 | |
| Pittsburgh | V | Henry Co, GA | ||
| Pittsburgh | PV | Johnson Co, AR | 680 | water by Arkansas river |
| Pittsburgh | PO | Darke Co, OH | ||
| Pittsburgh | PO | Van Buren Co, IA | ||
| Pittsburgh | PO | Hickory Co, MO | ||
| Pittsfield | PT | Somerset Co, ME | 1,176 | water by tributary of Sebasticook river |
| Pittsfield | PT | Rutland Co, VT | 512 | water by Tweed river |
| Pittsfield | PT | Merrimack Co, NH | 1,828 | water by Suncook river |
| Pittsfield | PT | Berkshire Co, MA | 5,872 | water by tributaries of Housatonic river |
| Pittsfield | PT | Otsego Co, NY | 1,591 | water by Unadilla river |
| Pittsfield | PO | Warren Co, PA | ||
| Pittsfield | PT | Lorain Co, OH | 1,088 | |
| Pittsfield | PT | Washtenaw Co, MI | 1,234 | |
| Pittsfield | PV, CH | Pike Co, IL | seat of justice | |
| Pittsford | PT | Rutland Co, no state (VT) | 2,026 | water by Otter creek & Furnace river |
| Pittsford | PT | Monroe Co, NY | 2,061 | water by Irondiquoit creek |
| Pittsford | PT | Hillsdale Co, MI | 1,232 | |
| Pittston | PT | Kennebec Co, ME | 1,967 | water by Kennebec river |
| Pittston Ferry | PO | Luzerne Co, PA | ||
| Pittstown | PT | Luzerne Co, PA | ||
| Pittstown | PT | Rensselaer Co, NY | 3,732 | water by Tomhannock creek & Hoosick river |
| Pittstown | PV | Alexander twp, Hunterdon Co, NJ | water by tributary if Raritan river | |
| Pittsylvania | PV, CH | Pittsylvania Co, VA | water by branch of Banister river | |
| Placerville | PO | El Dorado Co, CA | ||
| Plain | T | Stark Co, OH | 2,211 | |
| Plain | T | Franklin Co, OH | 1,561 | |
| Plain | T | Wood Co, OH | 492 | |
| Plain | T | St Francis Co, AR | ||
| Plain | PT | Wayne Co, OH | 2,375 | |
| Plain | PO | Greenville dist, SC | ||
| Plain Grove | PO | Lawrence Co, PA | ||
| Plain View | PO | Macoupin Co, IL | ||
| Plain View | PO | King and Queen Co, VA | ||
| Plainfield | PT | Sullivan Co, NH | 1,391 | water by Connecticut river |
| Plainfield | PT | Washington Co, VT | 808 | water by Onion river & Great brook |
| Plainfield | PT | Hampshire Co, MA | 814 | water by head waters of Westfield river & North pond |
| Plainfield | PT | Windham Co, CT | 2,732 | water by Quinnebaug & Moosup rivers |
| Plainfield | PT | Otsego Co, NY | 1,450 | water by Unadilla river |
| Plainfield | PV | Westfield twp, Essex Co, NJ | 2,446 | water by Green brook |
| Plainfield | T | Northampton Co, PA | 1,753 | water by east branch of Bushkill creek |
| Plainfield | PV | Linton twp, Coshocton Co, OH | water by Willis creek | |
| Plainfield | T | Allegan Co, MI | ||
| Plainfield | PO | Livingston Co, MI | ||
| Plainfield | PT | Hendricks Co, IN | ||
| Plainfield | PT | Will Co, IL | 1,093 | |
| Plainfield | PO | Cumberland Co, PA | ||
| Plainsborough | PO | Middlesex Co, NJ | ||
| Plains of Dura | PO | Sumter Co, GA | ||
| Plainsville | PO | Exeter twp, Luzerne Co, PA | ||
| Plainville | PO | Farmington twp, Hartford Co, CT | ||
| Plainville | PV | Lysander twp, Onondaga Co, NY | ||
| Plainville | PO | Hamilton Co, OH | ||
| Plainwell | PO | Allegan Co, MI | ||
| Plaistow | PT | Rockingham Co, NH | 748 | |
| Plank Road | PO | Onondaga Co, NY | ||
| Plank Road | PT | Wayne Co, MI | ||
| Planters | PO | Attala Co, MS | ||
| Planters | PT | Phillips Co, AR | 687 | |
| Planters' Hall | PO | Breckenridge Co, KY | ||
| Planters' Stand | PO | Madison Co, GA | ||
| Plantersville | PV | Perry Co, AL | ||
| Plaquemine | PV, CH | Iberville parish, LA | water by Mississippi river | |
| Plaquemine Brulee | PO | St Landry parish, LA | ||
| Platea | PO | Erie Co, PA | ||
| Plateau | T | Jefferson Co, MO | ||
| Plato | PO | Amherst twp, Lorain Co, OH | ||
| Plato | PO | Cattaraugus Co, NY | ||
| Plato | PO | Iroquois Co, IL | ||
| Platte | T | Buchanan Co, MO | ||
| Platte City | PV, CH | Platte Co, MO | 881 | seat of justice, water by Little Platte river |
| Platte River | PO | Buchanan Co, MO | ||
| Plattekill | PT | Ulster Co, NY | 1,998 | water by Old Man's kill & tributaries of Wall kill |
| Platteville | PV | Grant Co, WI | ||
| Plattsburgh | PT, CH | Clinton Co, NY | 5,618 | seat of justice, water by Saranac river & Lake Champlain |
| Plattsburgh | PV, CH | Clinton Co, MO | seat of justice, water by Smith's fork of Platte river | |
| Plattville | PO | Kendall Co, IL |