| Sept | Clan | |
| Magee | Donald | From Islay, Kintyre or Antrim and must have originally been a MacKay of Islay (103) |
| Magee | Sutherland | |
| Magill | Donald | Only those known to have originally been MacGills |
| Makartane | 13th & 14th Century Scottish Names Gaelic bynames are as Chiefly titles, not as simple patronymics. | |
| Malcolmson | MacCallum | |
| Malcolmson | Malcolm | |
| Malloch | MacGregor | |
| Mandeville | 13th & 14th Century Scottish Names of Mavndwell, Mawndwil | |
| Mann | Donald | Only those from Lochaber and must have originally been a MACGILLIVANTIC. Approx. 24% of all Manns are of Scots ancestry.1 in 250 may be of Clan Donald |
| Mann | Gunn | Or, from Aberdeen, Brechin, Dundee or Dingwall |
| Manntach | Donald | Only those from Lochaber and must have originally been a MACGILLIVANTIC |
| Manson | Gunn | |
| Marcus | Donald | From Kintyre and must have originally been a MACMARCUS. Scots Marcus' not of Clan Donald may be from Inverness. 1 in 20 may be of Clan Donald. |
| Marcusson | Donald | From Kintyre and must have originally been a MACMARCUS. Scots Marcussons not of Clan Donald may be from Aberdeen or Shetland. |
| Mark | MacDonald | |
| Marnoch | Innes | |
| Mar | 13th & 14th Century Scottish Names of Mar | |
| Marr | Gordon | |
| Marshall | Keith | |
| Martin | Cameron | Or, from Lothian or Angus |
| Martin | Donald | Only those from Skye or N. Uist, Islay or Kintyre. Approx. 31% of all Martins are of Scots ancestry. 1 in 15 may be of Clan Donald. |
| Martin | MacDonald | |
| Marthokys | 3th & 14th Century Scottish Names of Marthokys | |
| Mason | Sinclair | |
| Massey | Matheson | |
| Masterson | Buchanan | |
| Mathie | Matheson | |
| Mavor | Gordon | |
| May | Donald | From West Highlands & Islands, mainly Kintyre(154). Approx. 8% of these names are of Scots ancestry. Scots Mays not of Clan Donald may be from Aberdeen, Berwick, Dunglas, Fife or Tweedside. 1 in 75 may be of Clan Donald. |
| May | MacDonald | |
| Mayes | Donald | From West Highlands & Islands, mainly Kintyre(154). Approx. 8% of these names are of Scots ancestry. Scots Mays not of Clan Donald may be from Aberdeen, Berwick, Dunglas, Fife or Tweedside. 1 in 75 may be of Clan Donald. |
| Mayle-Erll |
13th & 14th Century Scottish Names Male-Erll, Mayle-Erll |
|
| Mays | Donald | From West Highlands & Islands, mainly Kintyre(154). Approx. 8% of these names are of Scots ancestry. Scots Mays not of Clan Donald may be from Aberdeen, Berwick, Dunglas, Fife or Tweedside. 1 in 75 may be of Clan Donald. |
| Means | Menzies | |
| Meikleham | Lamont | |
| Meine | Menzies | |
| Megues | Menzies | |
| Mennie | Menzies | |
| Mentieth | Graham | |
| Meyners | Menzies | |
| Michael | Donald | From West Highlands & Islands and must have originally been a MACMICHAEL. Approx. 24% of all Michaels are of Scots ancestry. Scots Michaels not of Clan Donald may be from Angus, Couper, Glasgow or St. Andrews. 1 in 210 may be of Clan Donald. |
| Michaelson | Donald | Only those from West Highlands & Islands and must have originally been a MACMICHAEL. Approx. 24% of all Michaels are of Scots ancestry. Scots Michaels not of Clan Donald may be from Aberdeen. |
| Michie | Donald | Only those from Lochaber and must have originally been a MACMICHIE. |
| Michie | Forbes | Michies not of Clan Donald may be of Clan Forbes, or, from Aberdeen. |
| Michison | Donald | Only those from Lochaber and must have originally been a MACMICHIE. |
| Michison | Forbes | Or from Aberdeen |
| Middleton | Innes | |
| Miller | MacFarlane | |
| Milloy | Donald | Only those from Kintyre and must have originally been a MACMALUAG |
| Milloy | Stewart | Or from Argyll, Arran or Bute |
| Milne | Gordon | |
| Milne | Ogilvy | |
| Milroy | MacGillivray | |
| Minn | Menzies | |
| Minnus | Menzies | |
| Mitchell | Donald | From West Highlands & Islands and must have originally been a MACMITCHELL. Approx. 73% of all Mitchells are of Scots ancestry. 1 in 80 may be of Clan Donald |
| Mitchell | Innes | Or, from Aberdeen, Dundee, Glasgow or Lanarkshire |
| Mitchelson | Donald | From West Highlands & Islands and must have originally been a MACMITCHELL. Scots Mitchelsons not of Clan Donald may be from Aberdeen, Brechin, Fife, Glasgow, Inverness, Kilbride or Shetland. |
| Moffat | 13th & 14th Century Scottish Names of Moffat, Mufhet, of Murref, of Murreff | |
| Moir | Gordon | |
| Monach | MacFarlane | |
| Monk | Donald | From N. Uist or Benbecula and must have originally been a MACMANECHIN. Scots Monks not of Clan Donald may be from Aberdeen, Berwick or Dysart. |
| Monteith | Graham | |
| Monzie | Menzies | |
| Moodie | Stewart | |
| Moray | Murray | |
| Morgan | MacKay | |
| Morren | MacKinnon | |
| Morris | Buchanan | |
| Morton | Douglas | |
| Mowbray | 13th & 14th Century Scottish Names of Mawpaß, the Mobray, Mowbra, the Mowbra, Mowbray, the Mowbray | |
| Mowat | Sutherland | |
| Muir | More | |
| Munn | Stewart, Lamont | |
| Murchie | Buchanan | Or, from Caithness, Irvine or Peebles |
| Murchie | Donald | From Islay, Kintyre or Antrim and must have originally been a MACMURCHIE. |
| Murchie | MacKenzie | Or, from Caithness, Irvine or Peebles |
| Murchie | Menzies | Or, from Caithness, Irvine or Peebles |
| Murchieson | Buchanan | |
| Murchieson | Menzies | |
| Murchison | Donald | From West Highlands & Islands or Antrim and must have originally been a MACMURCHIE. Murchisons not of Clan Donald may be of Clans Buchanan or MacKenzie, or, from Caithness, Irvine or Peebles. |
| Murdoch | Donald | From West Highlands & Islands or Antrim |
| Murdoch | MacDonald | |
| Murdoch | MacPherson | |
| Murdochson | Donald | From West Highlands & Islands or Antrim |
| Murdochson | MacPherson | Or from Brechin, Perth or Shetland |
| Murdoson | MacDonald | |
| Murdoson | MacPherson | |
| Murphy | Donald | Only those from Islay, Kintyre or Antrim and must have originally been a MACMURCHIE. Approx 7% of all Murphys are of Scots ancestry. 1 in 285 may be of Clan Donald. |
| Murphy | MacDonald | |