| Maaß (M000) | | | | bethanyleigh |
| MacE (M200) | Brigstock | 1680 | | Tassie Devil |
| MacKonochie (M252) | Dorset. London, Scotland, India | 1750 | 1900 | luxmalc |
| MacPherson (M216) | Lancashire | 1830 | 1880 | Merry |
| Madden (M350) | Roma Qld Brisbane and Redcliffe, Brisbane Qld Aust | 1880 | 1968 | MacPanda |
| Maddock (M320) | Herts Beds | 1750 | 1840 | Oakum Picker |
| Madlock (M342) | Worldwide | | | medlockons |
| Malbon (M415) | Derbyshire and Cheshire | 1600 | 1850 | Gert in Oz |
| Malkin (M425) | Yorkshire | 1800 | 1950 | Jojob |
| Mallatratt (M436) | cambridge | 1500 | | teddybr |
| Mallatratt (M436) | Godmanchester, Huntingdonshire and Huntingdonshire area | 1760 | 1830 | ElizabethHerts |
| Mallatratt (M436) | Hertfordshire | 1550 | 1800 | ElizabethHerts |
| Mallet (M430) | Lichfield, Staffordshire | | | Mary from Italy |
| Mallett (M430) | Norfolk / Suffolk / London | 1700 | 1900 | Jazzycat |
| Manclarke (M524) | Norfolk | 1500 | 1800 | Guinevere |
| Mann (M500) | North Elmham/Horningtoft/Brisley | 1715 | 1800 | Janet in Yorkshire |
| Manning (M552) | Nobottle, Northamptonshire | 1600 | 1700 | SHoward |
| Marbury (M616) | Alford (Lincolnshire) | | | bethanyleigh |
| Marchant (M625) | Hinxworth, Hitchin, Hertfordshire | 1680 | 1720 | Merry |
| Mardale (M634) | Farmborough, Somerset | 1750 | 1800 | Merry |
| Marlow (M640) | Walsall, Staffordshire | 1780 | 1800 | Merry |
| Marsden (M623) | City of London & Shoreditch | 1800 | 1900 | Nell |
| Marsden (M623) | Essex | 1750 | 1800 | Nell |
| Marshall and Spelling Variations (M624) | Grendon, Northamptonshire | 1550 | 1750 | ElizabethHerts |
| Martin (M635) | Brighton, Sussex | 1840 | | marquette |
| Martin (M635) | Cornwall - Sithney, Gerrans, St. Keverne | 1680 | 1750 | |
| Martin (M635) | Herts | 1600 | 1680 | Oakum Picker |
| Martin (M635) | Killean, Argyll | 1740 | 1780 | Shona |
| Mason (M250) | Ashby de la Zouch, Leicestershire | 1730 | 1800 | Margaret in Burton |
| Mason (M250) | Herts | 1650 | 1740 | Oakum Picker |
| Mason (M250) | Newcastle under Lyme, Staffordshire | 1750 | | Anne in North London |
| Massingham (M252) | Cley next the sea, Norfolk | 1720 | 1785 | Phoenix |
| Massingham (M252) | Langham, Norfolk | 1670 | 1870 | Nell |
| Matthews (M320) | Shoreditch | 1730 | 1900 | Sue from Southend |
| Matthews (M320) | Tasmania ? | 1872 | 1948 | Tassie Devil |
| Matthews (M320) | Whichford, Warwickshire | 1700 | 1899 | Nell |
| Mattock/S (M320) | Suffolk | 1700 | 1900 | Jazzycat |
| Maunder (M536) | St. Cleer / St. Neot, Cornwall | 1810 | 1950 | RavKen |
| May (M000) | Ohio | 1920 | 1922 | Jbeech |
| Mayall (M400) | Prestbury & Southam, Gloucestershire | | | Vivian |
| Mayhew (M000) | Suffolk | 1760 | 1820 | Oakum Picker |
| Maynard (M563) | Bermondsey | 1600 | 1800 | Cass Ainslie |
| Maynard (M563) | Kempston, Bedfordshire | 1730 | 1850 | Merry |
| Maynard (M563) | Whittlesford, Cambridgeshire | 1790 | 1920 | Merry |
| McBrierty (M216) | Ireland, and South Australia | | | Pinefamily |
| McBroom (M216) | ARM Ireland and Brighton Victoria Australia | 1830 | 1916 | MacPanda |
| McBryde (M216) | Ireland | 1770 | 1822 | JBee |
| McCallum (M245) | Irvine and Kilmarnock, Ayrshire | 1790 | 1850 | Shona |
| McCallum (M245) | Killean, Argyll | 1770 | 1800 | Shona |
| McCarten (M263) | Downpatrick, Do Down | 1790 | 1850 | Shona |
| McCaskill (M224) | Inverness | 1800 | | Olde Crone |
| McClannan (M245) | Liverpool/Birkenhead | 1820 | 1900 | Murphy |
| McClellan (M244) | Ohio | | | LouHummerSally |
| McCrery (M266) | Bedfordshire, Middlesex and London | 1750 | 1850 | Merry |
| McCrohon (M265) | Australia | 1832 | 2016 | mccrohons |
| McCrohon (M265) | Australia, NSW - Inverell, Tingha, Maitland, Sydney | 1835 | 1940 | |
| McCrohon (M265) | Limerick | 1795 | 1805 | mccrohons |
| McCrohon (M265) | Portugal | 1827 | 1830 | |
| McCrudden (M263) | Co Monaghan, Ireland | 1800 | 1900 | Shona |
| McDonagh (M235) | Ben Lomond, NSW | 1870 | 1970 | |
| McDonagh (M235) | Gurtigara, Gurteen, Co Sligo, Ireland | 1830 | 1970 | |
| McDonough (M235) | Co Galway/Northumberland | 1830 | 1900 | Janet in Yorkshire |
| McDougall (M232) | Lancashire, Scotland | | | Zoemcdougall |
| McGilthighnich (M243) | Islay | 1745 | 1800 | JBee |
| McGlary (M246) | Anywhere | 1800 | 1950 | Shona |
| McGloghlan (M242) | | | | Daphne |
| McGuire (M260) | County Tyrone Ireland, and South Australia | 1857 | | Pinefamily |
| McIntyre (M253) | Killean, Argyll | 1780 | 1820 | Shona |
| McIntyre (M253) | South Uist | 1600 | 1900 | Canucky Woman |
| McIsaac (M222) | Campbeltown, Argyll | 1690 | 1950 | Shona |
| McIsaac (M222) | Killean, Argyll | 1850 | 1930 | Shona |
| McIsaac (M222) | South Knapdale | 1790 | 1800 | Shona |
| McIsaac (M222) | Southend, Argyll | 1750 | 1850 | Shona |
| McKenzie (M252) | Westmoreland, Northumberland | | | JBee |
| McKinlay (M254) | Killean, Argyll | 1790 | 1820 | Shona |
| McKinnon (M255) | Eigg | | | Annickburn |
| McLaughlan (M242) | Culfeightrin?, Co Antrim | 1800 | 1830 | Shona |
| McLaughlan Mclagloughlin (M242) | Innishmagrath, Co Leitrim | 1800 | | JBee |
| McLean (M245) | Campbeltown, Argyll | 1750 | 1900 | Shona |
| McLean (M245) | Killean, Argyll | 1750 | 1900 | Shona |
| McMillan (M254) | Clachan, Argyll | 1750 | | JBee |
| McMillan (M254) | Colonsay | 1791 | 1872 | Annickburn |
| McMinn (M255) | Lisball, Cavan, Ireland | 1800 | 1910 | j9diabolo |
| McMullen (M254) | Antrim | 1814 | 1870 | daisynook |
| McMurchy, Mcmurchie (M256) | Clachan, Argyll | | | JBee |
| McMurchy/Mcmurphy (M256) | Clachan, South Knapdale, Argyll | 1770 | 1800 | Shona |
| McNair (M256) | Glasgow Scotland | | | Quirkey |
| McNair (M256) | Killean, Argyll | 1700 | 1820 | Shona |
| McNaught (M252) | dumfriesshire | 1750 | 1900 | mcnaught |
| McNaughton, Macnaughton (M252) | Scotland, Canada, USA, Australia | 1700 | 1950 | Jojob |
| McNeil (M254) | hoddam, Dumfrieshire | 1680 | 1870 | j9diabolo |
| McNeill (M254) | Isle of Colonsay, Argyll | 1800 | 1820 | Shona |
| McNiven (M251) | Killean, Argyll | 1700 | 1750 | Shona |
| McQuade, Mcquaid (M235) | Ireland | | | JBee |
| McStalker/Stalker (M234) | Killean, Argyll | 1770 | 1790 | Shona |
| McWilliam(S) (M245) | Morayshire | 1800 | | Olde Crone |
| Meadon (M350) | Staffordshire | 1750 | | Anne in North London |
| Meadows (M320) | London, Manchester | 1700 | 1930 | Canucky Woman |
| Mealing (M452) | Gloucestershire | 1700 | 1900 | Nell |
| Mear (M600) | Burton-upon-Trent, Staffordshire | 1650 | 1700 | Merry |
| Mear (M600) | Devon - Sandford | 1760 | | Langley Vale Sue |
| Mears (M620) | Maitland / Cobar NSW Aust | 1900 | 1942 | LordByronBay |
| Medlock (M342) | Worldwide | | | medlockons |
| Melia (M400) | Lancashire, & Boston USA | | | Zoemcdougall |
| Mellor (M460) | Slaithwaite, Yorkshire | 1705 | | |
| Mellor (M460) | Warwickshire | 1750 | 1900 | Guinevere |
| Mellsop (M421) | Ireland | 1700 | 1870 | melodi2 |
| Melville (M414) | Paisley, Glasgow and New Zealand | | 1950 | DavidByrne |
| Meredith (M633) | Herefordshire | | | Nona |
| Meredith (M633) | Wombourne, Staffordshire | 1750 | 1800 | Merry |
| Merrick (M620) | herefordshire | 1600 | 1900 | garstonite |
| Meuros/S (M620) | Denham/Wycombe Bucks and Scotland | 1750 | 1900 | Jazzycat |
| Meyer (M600) | Bavaria | | | bethanyleigh |
| Midgely (M324) | Halifax | 1700 | 1900 | rachelagourakis |
| Midmore (M356) | Rotherfield and Mayfeild Sussex | 1733 | 1819 | |
| Midwinter (M353) | Bloxham, Oxfordshire | 1750 | 1800 | Merry |
| Mignault Dit Labrie (M254) | | | | bethanyleigh |
| Miles (M420) | Surrey | 1740 | 1800 | ElizabethHerts |
| Millard (M463) | Dorset, Gussage | 1800 | 1900 | Langley Vale Sue |
| Miller (M460) | Edinburgh | 1780 | 1850 | nslattery |
| Milloy (M400) | Killean, Argyll | 1700 | 1950 | Shona |
| Mills (M420) | Gloucestershire | 1780 | | Margaret in Burton |
| Mills (M420) | March, Cambridgeshire | 1800 | 1870 | Skippy |
| Mills (M420) | Scotland - Kilbarchan area, Renfrewshire | 1700 | 1850 | Langley Vale Sue |
| Millwood (M430) | Middlesex | 1780 | 1880 | Merry |
| Minshull (M524) | Staffordshire | 1800 | 1850 | |
| Mitchelhill (M324) | Selkirk: Kirkcudbright: London | | | Ann from Sussex |
| Mitchell (M324) | Cuckfield | 1880 | 1900 | Stevebbh |
| Mitchell (M324) | Cuckfield, Sussex | 1650 | 1950 | Jill |
| Mitchell (M324) | Gladsmuir, Leith, Midlothian | | | JBee |
| Mitchell (M324) | Horfield, Gloucestershire | 1810 | 1900 | Merry |
| Mitchell (M324) | Keynsham, Somerset | 1815 | 1900 | Merry |
| Mitchell (M324) | Lindfield | 1870 | 1920 | Stevebbh |
| Mitchell (M324) | NSW | 1830 | | MuzzaKiwi |
| Mitchell (M324) | Powassan, Canada | 1911 | 1940 | Jill |
| Mitchell (M324) | Redhill Surrey | 1870 | 1930 | JessBow |
| Mitchell (M324) | Witney, Oxfordshire | 1790 | 1800 | Merry |
| Moffat (M130) | Campbeltown, Argyll | 1860 | 1900 | Shona |
| Moffat (M130) | Southend, Argyll | 1840 | 1860 | Shona |
| Molck (M420) | Germany | | | catfordcrooner |
| Moncur (M526) | Aberdeen | 1800 | | Olde Crone |
| Montgomery (M532) | Ayrshire | 1700 | 1750 | Shona |
| Moody (M300) | Scotter and surrounding area, Lincolnshire | 1550 | 1620 | ElizabethHerts |
| Moody (M300) | Spalding/Holbeach Lincolnshire | 1780 | 2014 | lincslady |
| Moorare/Moorar/Morar/Morer (M665) | Headley, Hampshire | 1545 | 1588 | |
| Moore (M600) | Boston, Lincolnshire & Sheffield | 1700 | 2013 | BlueSavannah |
| Moore (M600) | Ireland, Australia | 1750 | 2000 | HarrysMum |
| Moore (M600) | Shoreditch | 1750 | 1920 | Sue from Southend |
| Moorhouse (M620) | Ashton Under Lyne, Lancashire | 1763 | | |
| Morand (M653) | Ireland | 1700 | 1800 | MaryManatee |
| Morgan (M625) | Gloucestershire - Charlton Kings | 1800 | 1900 | Langley Vale Sue |
| Morgan (M625) | Shiplake, Caversham, Oxfordshire | 1730 | 1800 | Merry |
| Morley (M640) | Heptonstall and area, Yorkshire | 1700 | 1850 | ElizabethHerts |
| Morley (M640) | Herts | 1700 | 1750 | Oakum Picker |
| Morris (M620) | Branston, Lincolnshire | 1680 | 1750 | ElizabethHerts |
| Morris (M620) | Kinghorn, Fife | 1775 | 1820 | Shona |
| Morris (M620) | Oxfordshire | 1600 | 1900 | RelativeStrangers |
| Mortimore (M635) | Devon | | | suen |
| Mortlock (M634) | Burton on Trent, Staffordshire | 1875 | | Margaret in Burton |
| Mortlock (M634) | Shimpling, Suffolk | 1750 | | Margaret in Burton |
| Moses (M220) | Cornwall, possibly St Enoder | 1500 | 1600 | ElizabethHerts |
| Moss/Morse (M256) | Mitcham, Surrey | 1744 | 1870 | Sue from Southend |
| Moule (M400) | Orwell, Cambridgeshire | 1700 | 1850 | Merry |
| Moult (M430) | Derbyshire and Hollingworth | 1600 | 1800 | ElizabethHerts |
| Moyes (M200) | Hillend, Fife | 1750 | 1890 | Shona |
| Moyse (M200) | Suffolk | 1750 | 1810 | Oakum Picker |
| Mugridge/Muggeridge (M263) | SUSSEX,ENGLAND | 1600 | | susan sayers |
| Mullaney (M450) | Liverpool and Ireland | 1800 | 1900 | Tilly Mint |
| Mullins (M452) | Covent Garden, London | 1800 | 1900 | Nell |
| Munday (M530) | Hampshire | | | bethanyleigh |
| Munns (M520) | Soham | 1700 | | HuntsLamb |
| Murray (M600) | RUTHWELL, DUMFRISHIRE, SCOTLAND | 1669 | 1760 | j9diabolo |
| Murton (M635) | Diss Norfolk/Shelfhanger Guisborough | 1800 | 1990 | |
| Mutler (M346) | London/ Cambridgeshire/ Lincolnshire/ nottinghamshire | 1700 | 2014 | lincslady |
| Myhill (M400) | Norfolk | | | Carolyn P |