| Family Names Being Researched | Period | Location:- City Town, Village or Region | County or State | Country | Membership Number |
| JACQUES John | c1650 | LIN | ENG | 10 | |
| JANCEY | 1695 + | Withington | HEF | ENG | 10 |
| JARVIS Robert | c1768 | Kettering | NTH | ENG | 478 |
| JARVIS Robert | c1840 | Desborough | NTH | ENG | 478 |
| JARVIS Thomas | 1845 - 1880 | Launceston | TAS | AUS | 478 |
| JARVIS Thomas | 1802 | Desborough | NTH | ENG | 478 |
| JAUNCY | 1694 + | Withington | HEF | ENG | 10 |
| JEFFERIES James | 1801 - 1829 | Keevil | WIL | ENG | 478 |
| JEFFREYS | pre 1860 | WIL | ENG | 404 | |
| JESSEP | 1870 + | Maffra | VIC | AUS | 30 |
| JESSEP | 1800 - 1900 | Swaffham | NOR | ENG | 30 |
| JESSUP William | 1857 - 1888 | Hermitage | SA | AUS | 478 |
| JOHNSON Elizabeth | 1780 - 1820 | CAM | ENG | 575 | |
| JOHNSON Mary | c1744 | Aughton | YKS | ENG | 19 |
| JONES | 1800 + | Liverpool | LAN | ENG | 323 |
| JONES | pre 1860 | London | LND | ENG | 404 |
| JOSSELYN | 1797 - 1844 | Belstead | SFK | ENG | 10 |
| KEIG | pre 1849 | IOM | ENG | 596 | |
| KEIG James | 1849 + | VIC | AUS | 596 | |
| KEMP | 1750 + | All | SFK | ENG | 323 |
| KENNEDY | c1892 | Masterton | NZ | 10 | |
| KENNEDY | pre 1853 | Kilmalie | INV | SCT | 10 |
| KENNEDY | 1854 - 1892 | Clunes | VIC | AUS | 10 |
| KENNEDY | 1854 - 1892 | Ballarat | VIC | AUS | 10 |
| KENNEDY | c1843 | Cullen | BAN | SCT | 566 |
| KENNEDY Duncan | 1875 - 1892 | Wychitella | VIC | AUS | 10 |
| KEWISH | pre 1849 | IOM | ENG | 596 | |
| KEWISH Catherine | 1849 + | VIC | AUS | 596 | |
| KINCAID | Pre 1800 | Falkirk | STI | SCT | 674 |
| KING | pre 1860 | Chatham | KEN | ENG | 404 |
| KING | pre 1860 | Geelong / Dunolly | VIC | AUS | 404 |
| KING | pre 1860 | Icklingham | SFK | ENG | 404 |
| KING | pre 1860 | Heathcote / Rushworth | VIC | AUS | 404 |
| KING / KINGE | 1559 + | Lavenham | SFK | ENG | 10 |
| KITCHINGHAM | 1815 + | Sittingborne | KEN | ENG | 30 |
| KITTLE | 1700 - 1800 | Raleigh | DEV | ENG | 641 |
| KUTCWITZ Anna | 1832 | Gross Schmollen | PRE | DEU | 478 |
| LALLY | c1800 | GAL | IRL | 19 | |
| LAMB | c1860 | Cullen | BAN | SCT | 566 |
| LANE | 1725 + | Pencombe | HEF | ENG | 10 |
| LANGHAM Edward | c1820 | ENG | 478 | ||
| LANGHAM Sarah Ann | 1864 - 1868 | Portsea Island, Southampton | HAM | ENG | 478 |
| LANGHAM Sarah Ann | 1889 | HKG | CHN | 478 | |
| LATHAM | 1850 + | Johnsonville | VIC | AUS | 666 |
| LATIMER Elizabeth | c1685 | Harrington, Albany | NTH | ENG | 478 |
| LAWRENCE | 1600 + | Mendlesham | SFK | ENG | 323 |
| LAWRENCE | 1800 + | Buchan / Bonang | VIC | AUS | 514 |
| LEARY James | 1863 | Launceston | TAS | AUS | 478 |
| LEE | 1800 + | Omeo | VIC | AUS | 514 |
| LEVERAGE | 1750 + | All | SFK | ENG | 323 |
| LILLY | c1740 | Deal | KEN | ENG | 19 |
| LINDSEY | 1800 + | Fremantle | WA | AUS | 6 |
| LITTLE | pre 1860 | MDX | ENG | 404 | |
| LIVINGSTONE | pre 1826 | Mull | ARL | SCT | 10 |
| LOCKHART | 1860 + | East Gippsland | VIC | AUS | 10 |
| LOCKWOOD | pre 1600 | Laversham | SFK | ENG | 10 |
| LUCKINS | 1870 + | East Gippsland | VIC | AUS | 10 |
| LUCKINS | 1902 - c1920 | Lower Hutt | NZ | 10 | |
| LUCKMAN Francis Marcellus | 1807 - 1874 | LAN | ENG | 616 | |