1850 Atlas
| Name | What | Place | Pop | Other |
| Harshmansville | PO | Montgomery Co, OH | ||
| Hart | T | Warwick Co, IN | 1,434 | |
| Hart Lot | PO | Onondaga Co, NY | ||
| Hartfield | PV | Chautauque twp, Chautauque Co, NY | ||
| Hartford | City | Hartford Co, CT | 17,966 | State Capital |
| Hartford | PT | Oxford Co, ME | 1,293 | |
| Hartford | PT | Windsor Co, VT | 2,159 | water by White, Waterqueechy & Connecticut rivers |
| Hartford | T | Susquehanna Co, PA | 1,258 | |
| Hartford | PT | Washington Co, NY | 2,051 | water by tributaries of Wood creek |
| Hartford | PV, CH | Ohio Co, KY | water by Rough creek | |
| Hartford | PT | Trumbull Co, OH | 1,258 | |
| Hartford | PT | Licking Co, OH | 1,426 | |
| Hartford | V | Pulaski Co, GA | water Ocumulgee river | |
| Hartford | PV | Ohio Co, IN | ||
| Hartford | T | Van Buren Co, MI | 296 | |
| Hartford | T | Pike Co, MO | ||
| Hartford | PO | Putnam Co, MO | ||
| Hartford | PV | Knox Co, IL | ||
| Hartford | PO | Forsyth Co, GA | ||
| Hartford | PO | Washington Co, WI | ||
| Harthegig | PO | Mercer Co, PA | ||
| Hartland | PT | Somerset Co, ME | 960 | |
| Hartland | PT | Windsor Co, VT | 2,063 | water by Connecticut & Waterqueechy rivers & Lull's brook |
| Hartland | PT | Hartford Co, CT | 848 | water by east branch of Farmington river |
| Hartland | PT | Niagara Co, NY | 3,028 | water by Johnson's & Eighteen Mile creeks |
| Hartland | PT | Huron Co, OH | 1,024 | |
| Hartland | PT | Livingston Co, MI | 996 | |
| Hartland | PV | McHenry Co, IL | ||
| Hartland | PO | Waukesha Co, WI | ||
| Hartleton | PV | Hartley twp, Union CO, PA | ||
| Hartley | PT | Union Co, PA | 2,142 | |
| Hartleyville | PO | Athens Co, OH | ||
| Hart's Grove | PT | Ashtabula Co, OH | 650 | |
| Hart's Location | PO | Coos Co, NH | situated on southern part of White Mts | |
| Hart's Mills | PO | Ripley Co, IN | ||
| Hart's Village | PV | Washington twp, Dutchess Co, NY | ||
| Hartshorn | PO | Orange Co, NC | ||
| Hartstown | PO | Crawford Co, PA | ||
| Hartsville | PV | Tyringham twp, Berkshire Co, MA | ||
| Hartsville | PV | Manlius twp, Onondaga Co, NY | ||
| Hartsville | PV | Bucks Co, PA | ||
| Hartsville | PV | Sumner Co, TN | water by Cumberland river | |
| Hartsville | PV | Bartholomew Co, IN | ||
| Hartsville | PO | Darlington dist, SC | ||
| Hartsville | PV, CH | Wright Co, WI | seat of justice, water by Wood's fork of Gasconade river | |
| Hartsville | PO | Stark Co, OH | ||
| Hartwellville | PO | Shiawassee Co, MI | ||
| Hartwick | PT | Otsego Co, NY | 2,352 | water by Otsego creek & Susquehanna river |
| Hartwick Seminary | PV | Hartwick twp, Otsego Co, NY | seat of Hartwick Literary & Theological seminary | |
| Hartwood | PO | Stafford Co, VA | ||
| Hartwood | PO | Autauga Co, AL | ||
| Harvard | PT | Worcester Co, MA | 1,630 | water by Stony & Nashua rivers |
| Harvard | PO | Delaware Co, NY | ||
| Harvey's | PO | Greene Co, PA | ||
| Harvey's Five Points | PO | Westmoreland Co, PA | ||
| Harvey's Point | PO | Polk Co, IA | ||
| Harvey's Store | PO | Charlotte Co, VA | ||
| Harveysburgh | PV | Wayne twp, Warren Co, OH | 330 | |
| Harveysville | PV | Luzerne Co, PA | ||
| Harwick | PT | Barnstable Co, MA | water by Herring river, Long pond & Atlantic ocean | |
| Harwickport | PO | Harwick twp, Barnstable Co, MA | ||
| Harwinton | PT | Litchfield twp, no co given, CT | Naugatuck & Lead Mines rivers | |
| Hasbrouck | PO | Sullivan Co, NY | ||
| Haskellville | PO | Lawrence Co, OH | ||
| Haskenville | PO | Steubin Co, NY | ||
| Haskinsville | PV | Green Co, KY | ||
| Hastings | PT | Barry Co, MI | seat of justice, water by Thorn Apple river | |
| Hastings | PT | Oswego Co, NY | 2,920 | water by Salmon creek & Oneida lake outlet |
| Hastings | PO | Richland Co, state not given | ||
| Hastings upon Hudson | PV | Yonkers twp, Westchester Co, NY | water by Hudson river | |
| Hastingsville | PO | Columbiana Co, OH | ||
| Hat | PO | Lancaster Co, PA | ||
| Hat Creek | PO | Campbell Co, VA | ||
| Hat Creek | T | Taney Co, MO | ||
| Hat Grove | PO | Warren Co, IL | ||
| Hatborough | PV | Moreland twp, Montgomery Co, PA | 601 | |
| Hatcher's | PO | Talladega Co, AL | ||
| Hatchy Turnpike | PO | Tippah Co, MS | ||
| Hatfield | PT | Hampshire Co, MA | 1,073 | water by Connecticut & Mill rivers |
| Hatfield | T | Montgomery Co, PA | 1,135 | water by Neshaminy & Towamensing creeks |