| William Somerville | 1675–1742 | 1 |
| Arnold Sommerfeld | 1868–1951 | 1 |
| K. E. Sonck | 1852–1937 | 1 |
| Shangjie Song | 1901–1944 | 1 |
| Yingxing Song | born 1587 | 1 |
| George Soper | 1870–1942 | 1 |
| James Hamlin Gardner Soper | 1877–1939 | 3 |
| W. R. (William Ritchie) Sorley | 1855–1935 | 1 |
| Charles Sotheran | 1847–1902 | 1 |
| G. (Georges) Soulié de Morant | 1878–1955 | 1 |
| Lucy Helen Muriel Soulsby | 1856–1927 | 1 |
| José Sourryère de Souillac | 1750–1820 | 1 |
| John Philip Sousa | 1854–1932 | 2 |
| Amadeu de Sousa-Cardoso | 1887–1918 | 1 |
| Eliza Allen Southall | 1823–1851 | 1 |
| Robert Southey | 1774–1843 | 6 |
| Charles Southwell | 1814–1860 | 2 |
| Jessie Eldridge Southwick | 1865–1957 | 1 |
| Emma Dorothy Eliza Nevitte Southworth | 1819–1899 | 8 |
| Henry Sessions Souttar | 1875–1964 | 1 |
| Émile Souvestre | 1806–1854 | 5 |
| Millicent Sowerby | 1878–1967 | 1 |
| John Lancaster Spalding | 1840–1916 | 2 |
| Thomas Alfred Spalding | born 1850 | 1 |
| Vincenzo Spampanato | 1873–1928 | 1 |
| John Spargo | 1876–1966 | 5 |
| Edwin Erle Sparks | 1860–1924 | 1 |
| W. H. (William Henry) Sparks | 1800–1882 | 1 |
| Frank H. (Frank Hamilton) Spearman | 1859–1937 | 2 |
| Andrew Learmont Spedon | 1831–1884 | 1 |
| Harold Speed | 1873–1957 | 1 |
| Lancelot Speed | 1860–1931 | 3 |
| Nell Speed | 1878–1913 | 2 |
| Felix Speiser | 1880–1949 | 2 |
| John Hanning Speke | 1827–1864 | 2 |
| Catherine Helen Spence | 1825–1910 | 2 |
| Edward Fordham Spence | 1860–1932 | 1 |
| Lewis Spence | 1874–1955 | 2 |
| Percy F. S. (Percy Frederick Seaton) Spence | 1868–1933 | 2 |
| Anna Garlin Spencer | 1851–1931 | 1 |
| Herbert Spencer | 1820–1903 | 2 |
| Ichabod S. (Ichabod Smith) Spencer | 1798–1854 | 1 |
| John C. (John Canfield) Spencer | 1788–1855 | 1 |
| Harold Spender | 1864–1926 | 1 |
| William A. Spicer | 1845–1913 | 1 |
| William Ambrose Spicer | 1865–1952 | 1 |
| M. H. (Marion Harry) Spielmann | 1858–1948 | 1 |
| Joseph Spillman | 1842–1905 | 1 |
| Benedictus de Spinoza | 1632–1677 | 12 |
| R. J. Spitz | 1889–1954 | 2 |
| John L. (John Louis) Spivak | 1897–1981 | 1 |
| Ainsworth Rand Spofford | 1825–1908 | 1 |
| Harriet Elizabeth Prescott Spofford | 1835–1921 | — |
| Lysander Spooner | 1808–1887 | 1 |
| Shearjashub Spooner | 1809–1859 | 2 |
| Charles Sprague | 1791–1875 | 1 |
| Homer B. (Homer Baxter) Sprague | 1829–1918 | 1 |
| Norman Springer | 1888–1974 | 1 |
| Caroline F. E. (Caroline Frances Eleanor) Spurgeon | 1869–1942 | 1 |
| Steven Spurrier | 1878–1961 | 1 |
| Johanna Spyri | 1827–1901 | 21 |
| Squire, John Collings, Sir | 1884–1958 | — |
| Maud Hunt Squire | born 1873 | 1 |
| J. Hector St. John de Crèvecoeur | 1735–1813 | 1 |
| J. Allen (James Allen) St. John | 1872–1957 | 3 |
| F. St. Mars | 1883–1921 | 1 |
| Gordon Stables | 1840–1910 | 2 |
| W. S. (Walter S.) Stacey | 1846–1929 | 10 |
| H. De Vere (Henry De Vere) Stacpoole | 1863–1951 | 3 |
| Ferdinand Staeger | 1880–1976 | 1 |
| P.-J. Stahl | 1814–1886 | 1 |
| Paul Stahr | 1883–1953 | 2 |
| Edgcumbe Staley | 1845–1903 | 1 |
| James Stalker | 1848–1927 | 3 |
| Richard Stallman | born 1953 | 1 |
| G. P. (Georgi Porfirievich) Stamatov | 1869–1942 | 1 |
| Mary Newton Stanard | 1865–1929 | 1 |
| Burt L. Standish | 1866–1945 | 12 |
| Charles Joseph Staniland | 1838–1916 | 3 |
| Henry M. (Henry Morton) Stanley | 1841–1904 | 2 |