| Surname | Country | State | County or Province | From | To | Member |
|---|---|---|---|---|---|---|
| Safstrom | Sweden | Kopparberg | Dalarna | 1844 | present | B027-1 |
| Sager | USA | Pennsylvania | 1842 | 1911 | M001-1 | |
| Sager | USA | Indiana | Warren County | 1842 | 1911 | M001-1 |
| Sager | USA | Illinois | Vermilion County | 1842 | 1911 | M001-1 |
| Samuelson | Sweden | Vadstena | 1793 | 1858 | L012-1 | |
| Santeler | Austria | S033-1 | ||||
| Santeler | USA | Illinois | Cook County | S033-1 | ||
| Santroch | Czech Republic | S035-1 | ||||
| Santroch | USA | Wisconsin | Kewaunee County | S035-1 | ||
| Santroch | USA | Illinois | Cook | 1840 | 1956 | S035-1 |
| Saona | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1550 | 1774 | J009-1 |
| Sarlat | France | Périgord | Dordogne | 1610 | 1690 | J009-1 |
| Sass | USA | Illinois | Cook County (Chicago) | 1873 | 1946 | B003-1 |
| Satterlee | USA | Pennsylvania | 1780 | 1820 | P003-2 | |
| Satterlee | USA | New York | Genesee County | 1810 | 1860 | P003-2 |
| Satterlee | USA | Ohio | 1840 | 1900 | P003-2 | |
| Sauvaigo | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1590 | 1749 | J009-1 |
| Schaack | Luxemberg | G015-1 | ||||
| Schabell | USA | B003-1 | ||||
| Schabelski | USA | Pennsylvania | Pittsburgh County | B003-1 | ||
| Schabinger | Germany | F006-1 | ||||
| Schabinger | USA | Illinois | F006-1 | |||
| Schaeffer | Germany | M026-1 | ||||
| Schaeffer | USA | New York | M026-1 | |||
| Schaeffer | USA | Michigan | M026-1 | |||
| Schauer | USA | Wisconsin | 1880 | 1920 | S034-1 | |
| Scherer | Germany | A002-1 | ||||
| Schild | Germany | 1800 | present | P010-1 | ||
| Schild | USA | Illinois | Cook County | 1883 | present | P010-1 |
| Schimmerling | Czech Republic | Moravia | 1700 | present | F010-1 | |
| Schinnagel | Germany | Prussia | 1900s | B031-1 | ||
| Schittli | Switzerland | 1680 | 1750 | B018-1 | ||
| Schlapfer | Switzerland | Appenzell | Rehetobel | 1715 | 1750 | B018-1 |
| Schmelzer | Germany | Rheinland | Stephanshausen | 1600 | present | S005-1 |
| Schmidt | Poland | Wabrzezno | 1700 | present | S017-1 | |
| Schmulbach | Germany | Hesse | 1870 | Y002-1 | ||
| Schneefus | A002-1 | |||||
| Schneible | Germany | O004-1 | ||||
| Schneider | Germany | Hessen | Darmstadt (Pfungstadt) | 1830 | 1900 | B018-1 |
| Schofield | Ireland | Galway | 1880 | 1920 | S034-1 | |
| Schofield | USA | Massachusetts | 1880 | 1920 | S034-1 | |
| Schulsuig | C020-1 | |||||
| Schultheis | Germany | Bermuthshain, Darmstadt | 1814 | 1870 | D011-1 | |
| Schultheis | USA | PA | Philadelphia | 1814 | 1870 | D011-1 |
| Schultz | Germany | Prussia | 1835 | 1953 | G009-1 | |
| Schultz | Germany | P013-1 | ||||
| Schultz | USA | Ohio | Lucas County | 1835 | 1953 | G009-1 |
| Schultz | USA | Missouri | Marion County | P013-1 | ||
| Schultz | USA | New York | Towanda County | 1835 | 1953 | G009-1 |
| Schumpert | Germany | 1750 | 1780 | B018-1 | ||
| Schumpert | USA | South Carolina | Newberry County | 1790 | 1935 | B018-1 |
| Schumpert | USA | Mississippi | Lee County | 1790 | 1935 | B018-1 |
| Schutte | Germany | Westphalia | Mehner, Masch | 1730 | 1830 | B018-1 |
| Schutz | K002-1 | |||||
| Scott | USA | New York | Seneca County | 1750 | 1840 | W004-1 |
| Scott | USA | Michigan | Van Buren (Keeler) County | 1840 | present | W004-1 |
| Scuffle | Ireland | Galway | 1880 | 1920 | S034-1 | |
| Seekamp | USA | Illinois | Cook County (Chicago) | 1903 | 1945 | B003-1 |
| Seibert | Germany (Prussia) | Schwepphausen | Meath | bef 1836 | 1836 | M019-1 |
| Seibert | USA | Ohio | bef 1868 | 1868 | M019-1 | |
| Seibert | USA | Illinois | 1868 | present | M019-1 | |
| Serocki | Prussia | Also Chicago | 1851 | 1947 | T004-1 | |
| Shaffer | USA | South Carolina | Newberry County | 1760 | 1830 | B018-1 |
| Shaw | A010-1 | |||||
| Sheets | M031-1 | |||||
| Sheetz | K002-1 | |||||
| Sheldon | USA | Massachusetts | N006-1 | |||
| Sheldon | USA | New York | N006-1 | |||
| Sheldon | USA | Illinois | N006-1 | |||
| Sheldon | USA | Iowa | N006-1 | |||
| Shimer | USA | Indiana | Randolph County | 1820 | present | O001-1 |
| Shimer | USA | Iowa | Jasper County | 1820 | present | O001-1 |
| Shimer | USA | Iowa | Hardin County | 1820 | present | O001-1 |
| Signe | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1640 | 1700 | J009-1 |
| Silvius | Germany | Palatine | 1713 | 1738 | N001-1 | |
| Silvius | USA | Pennsylvania | Northampton County | 1738 | 1800 | N001-1 |
| Silvius | USA | Pennsylvania | Westmorland County | 1800 | 1900 | N001-1 |
| Simonsen | Denmark | Droninglund | 1855 | J009-1 | ||
| Simonsen/Simonson | USA | Iowa | J009-1 | |||
| Simonsen/Simonson | USA | Minnesota | J009-1 | |||
| Simpson | USA | PA | Fayette | 1790 | Present | B020-1 |
| Simsic | O004-1 | |||||
| Sisk | USA | Kentucky | P013-1 | |||
| Siudzinski | USA | Illinois | Cook County (Chicago) | 1873 | 1945 | B003-1 |
| Siudzinski | USA | Wisconsin | Brown County (Green Bay) | 1880 | present | B003-1 |
| Siudzinski | USA | Wisconsin | Two Rivers County | 1918 | 1950 | B003-1 |
| Skaer | Germany | Rhineland | Merxheim | 1840 | 1862 | P003-1 |
| Skaer | USA | Illinois | St. Clair County | 1736 | 1876 | P003-1 |
| Skjolaas | Norway | 1800 | present | A010-1 | ||
| Skjolaas | USA | Wisconsin | Dane County | 1800 | present | A010-1 |
| Skogsberg | Sweden | Varmland | 1839 | 1934 | O001-1 | |
| Skogsberg | USA | Minnesota | Goodhue County | 1839 | 1934 | O001-1 |
| Skogsberg | USA | Minnesota | Lake County | 1839 | 1934 | O001-1 |
| Smidt | Netherlands | Groningen | Middelstum | 1862 | 1940 | S029-1 |
| Smigiel | Poland | Poznan | Znin | 1760 | Present | K022-1 |
| Smigiel | USA | Michigan | 1880 | Present | K022-1 | |
| Smigiel | USA | Illinois | 1880 | Present | K022-1 | |
| Smith | USA | Illinois | Edgar County | 1800s | A001-1 | |
| Smith | A010-1 | |||||
| Smith | USA | South Carolina | Newberry County | 1720 | 1820 | B018-1 |
| Smith | USA | New York | Suffolk | 1950 | Present | F014-1 |
| Smith | G013-1 | |||||
| Smith | USA | South Carolina | Iredell County | 1830 | Present | H014-1 |
| Smith | Ireland | Armagh | 1830 | 1870 | J005-2 | |
| Smith | Sweden | 1870 | present | M023-1 | ||
| Smith | USA | Illinois | Cook County (Chicago) | M023-1 | ||
| Smith | USA | Texas | 1850 | present | S016-1 | |
| Smith | USA | Kentucky | Jefferson County | 1800s | A001-1 | |
| Smith | USA | Missouri | Middletown County | 1873 | Present | H014-1 |
| Smith | USA | Oklahoma | 1850 | present | S016-1 | |
| Smith | USA | Missouri | Audrain County | 1916 | Present | H014-1 |
| Smothers | USA | PA | Fayette | 1800 | 1920 | B020-1 |
| Smythe | England | 1843 | 1916 | D011-1 | ||
| Snider | A001-1 | |||||
| Snyder | USA | Illinois | Douglas County | 1850s | A001-1 | |
| Snyder | M026-1 | |||||
| Snyder | USA | Illinois | Cook County | 1900 | A001-1 | |
| Soraghan | Ireland | County Cavan | Denn, Dennbane | 1810 | present | B026-2 |
| Sorensen | Denmark | Ulsted | Alborg | 1868 | J009-1 | |
| Sorensen/Sorenson | USA | Minnesota | J009-1 | |||
| Spalding | K002-1 | |||||
| Sparks | USA | Tennessee | S034-2 | |||
| Spaulding | K002-1 | |||||
| Spaulding | USA | Connecticut | Windham County | 1700 | 1800 | T009-1 |
| Spitzer | Czech Republic | Moravia | 1700 | present | F010-1 | |
| Sporleder | A008-1 | |||||
| Sprugel | K002-1 | |||||
| Spurrier | USA | Tennessee | Sumner County | 1830 | 1880 | C022-1 |
| Sroczynski | Germany/Poland | Poznan | 1862 | 1890 | R003-1 | |
| Sroczynski | USA | Pennsylvania | Philadelphia County | 1890 | 1911 | R003-1 |
| Srozinski | USA | Pennsylvania | Philadelphia County | 1890 | 1911 | R003-1 |
| Srozinski | USA | North Dakota | 1911 | 1939 | R003-1 | |
| Staats | S003-1 | |||||
| Stabile/Stable | France | Provence-Alpes-Côte-d'Azur | Alpes-Maritimes | 1580 | 1762 | J009-1 |
| Stack | Ireland | F006-2 | ||||
| Stack | Ireland | M019-1 | ||||
| Stack | USA | M019-1 | ||||
| Stadler | USA | Wisconsin | Manitowoc County | B016-1 | ||
| Starner | USA | Iowa | 1850 | 1900 | R008-1 | |
| Stebbins | USA | New York | 1780 | 1920 | D005-1 | |
| Stebbins | USA | Connecticut | 1780 | 1920 | D005-1 | |
| Stebbins | USA | Wisconsin | Barron County | 1780 | 1920 | D005-1 |
| Stein | Germany | Helmsheim | 1700 | 1850 | S009-1 | |
| Stein | USA | Illinois | Wayne County | 1850 | present | S009-1 |
| Stein | USA | Illinois | White County | 1850 | present | S009-1 |
| Steinke | Germany | 1800 | 1860 | B018-1 | ||
| Stepien | Poland | City Keblow | 1860 | present | M030-1 | |
| Stepien | USA | IN | City LaPorte | 1860 | present | M030-1 |
| Stepien | USA | IL | City Chicago | 1860 | present | M030-1 |
| Stevens | USA | West Virginia | 1780 | A007-1 | ||
| Stevens | USA | Pennsylvania | 1780 | A007-1 | ||
| Stevens | USA | Ohio | 1780 | A007-1 | ||
| Stewart | USA | Pennsylvania | Tioga County | 1860 | W006-1 | |
| Stodolny | USA | Illinois | Cook County (Chicago) | S016-1 | ||
| Stoeckig | W019-1 | |||||
| Storer | Ireland | 1730 | 1780 | P003-2 | ||
| Storer | USA | Maine | Cumberland County | 1770 | 1830 | P003-2 |
| Storer | USA | Ohio | Cuyahoga County | 1830 | 1900 | P003-2 |
| Stormer | USA | Ohio | Lucas County | 1880 | present | A009-1 |
| Stormer | USA | Ohio | Seneca County | 1850 | 1875 | A009-1 |
| Storts | S003-1 | |||||
| Stotts | S003-1 | |||||
| Stroschien | USA | Illinois | B016-1 | |||
| Stubbins | USA | Maryland | Baltimore County | 1700 | 1850 | N001-1 |
| Stubbins | USA | Ohio | Harrison County | 1820 | 1900 | N001-1 |
| Stubbins | USA | Ohio | Jefferson County | 1857 | 1905 | N001-1 |
| Stubbins | USA | Ohio | Tuscarawas County | 1840 | 1900 | N001-1 |
| Stubbins | USA | Ohio | Columbiana County | 1880 | present | N001-1 |
| Stubbs | M031-1 | |||||
| Stuenkel | Germany | K019-1 | ||||
| Suffern | USA | New York | Rockland County | 1765 | present | H012-1 |
| Sugel | USA | Illinois | Cook County | 1900 | 1950 | B023-1 |
| Sulinski | Russia/Poland | Rogowo Parish | 1886 | 1904 | R003-1 | |
| Sulinski | USA | Illinois | Cook County | 1904 | 1934 | R003-1 |
| Sullivan | Ireland | County Cavan | Denn, Dennbane | 1810 | 1840s | B026-2 |
| Sullivan | USA | Pennsylvania | Northhampton County | 1840 | 1850 | B026-2 |
| Sullivan | USA | Pennsylvania | Williams County | 1840 | 1850 | B026-2 |
| Sullivan | USA | Illinois | Cook County (Chicago) | 1850 | present | B026-2 |
| Svajlenka | Czechoslovakia | F011-1 | ||||
| Svenskerud | A010-1 | |||||
| Svidron | Slovakia | W020-1 | ||||
| Svidron | USA | MN | 1880 | present | W020-1 | |
| Swift | USA | Illinois | Dekalb County | 1850 | 1950 | T009-1 |
| Sylvis | USA | Pennsylvania | Westmorland County | 1800 | 1900 | N001-1 |
| Sylvis | USA | Pennsylvania | Indiana County | 1830 | 1900 | N001-1 |
| Syoen | Belgium | bef 1800 | M019-1 | |||
| Syoen | USA | Illinois | Fayette County | bef 1920 | 1920 | M019-1 |
| Syoen | USA | Illinois | Cook County | 1920 | present | M019-1 |