| Malachi HouseEIN 34-1598707 | Human Services | OH | $1,410,317Small | 77.65 |
| Malaria No More FundEIN 20-5664575 | International | WA | $12,697,093Mid-sized | 92.14 |
| Maltz Museum of Jewish HeritageEIN 04-3684531 | Arts, Culture, Humanities | OH | $3,165,496Small | 85.21 |
| Mama's KitchenEIN 33-0434246 | Human Services | CA | $2,555,149Small | 78.24 |
| Man in the MirrorEIN 59-3178628 | Religion | FL | $3,291,289Small | 91.04 |
| Management Leadership for TomorrowEIN 52-1795164 | Human Services | MD | $10,079,879Mid-sized | 87.58 |
| Manatee Performing Arts CenterEIN 59-1196043 | Arts, Culture, Humanities | FL | $2,418,900Small | 94.85 |
| Manhattan Beach Education FoundationEIN 95-3881166 | Education | CA | $7,199,358Mid-sized | 96.25 |
| Manhattan Institute for Policy ResearchEIN 13-2912529 | Research and Public Policy | NY | $18,832,278Large | 94.25 |
| Manhattan Theatre ClubEIN 23-7086643 | Arts, Culture, Humanities | NY | $27,356,114Large | 90.34 |
| MANNAEIN 23-2586142 | Human Services | PA | $4,868,136Mid-sized | 91.49 |
| Manna Food CenterEIN 52-1289203 | Human Services | MD | $8,020,631Mid-sized | 95.70 |
| Manna Food PantriesEIN 59-2181031 | Human Services | FL | $1,417,371Small | 76.76 |
| MANNA FoodBankEIN 58-1514800 | Human Services | NC | $29,637,910Large | 99.10 |
| Manna on Main StreetEIN 23-2287252 | Human Services | PA | $2,603,058Small | 87.92 |
| MANNA WorldwideEIN 75-2931604 | International | TX | $6,474,131Mid-sized | 95.47 |
| Mano a Mano InternationalEIN 41-1796971 | International | MN | $2,440,095Small | 91.32 |
| ManometEIN 22-3051362 | Environment | MA | $4,959,830Mid-sized | 89.86 |
| Manos De CristoEIN 74-2511974 | Human Services | TX | $3,304,940Small | 94.69 |
| Manship TheatreEIN 20-3999559 | Arts, Culture, Humanities | LA | $2,015,238Small | 72.39 |
| Maoz Israel MinistriesEIN 51-0210369 | Religion | TX | $5,108,464Mid-sized | 92.81 |
| MAP InternationalEIN 36-2586390 | International | GA | $638,842,264Large | 100.00 |
| MapLightEIN 33-1094233 | Human and Civil Rights | CA | $2,988,723Small | 89.96 |
| Maranatha Volunteers InternationalEIN 38-1945104 | Religion | CA | $12,412,689Mid-sized | 88.14 |
| Marathon KidsEIN 06-1722171 | Human Services | TX | $2,921,366Small | 95.34 |
| March of DimesEIN 13-1846366 | Health | VA | $152,470,269Large | 73.14 |
| Marcus Jewish Community Center of AtlantaEIN 58-0566126 | Human Services | GA | $24,778,839Large | 90.20 |
| Marian HouseEIN 52-1243849 | Human Services | MD | $3,076,163Small | 90.13 |
| Marian Middle SchoolEIN 43-1873629 | Education | MO | $1,735,400Small | 90.04 |
| Marijuana Policy Project FoundationEIN 52-1975211 | Research and Public Policy | DC | $2,866,841Small | 77.62 |
| Marin Theatre CompanyEIN 23-7018125 | Arts, Culture, Humanities | CA | $3,690,566Mid-sized | 91.78 |
| Marine Biological LaboratoryEIN 04-2104690 | Research and Public Policy | MA | $42,842,812Large | 86.19 |
| Marine Conservation InstituteEIN 91-1725640 | Environment | WA | $1,068,198Small | 81.68 |
| Marine Corps Association FoundationEIN 80-0340923 | Human Services | VA | $1,536,917Small | 71.95 |
| Marine Corps Scholarship FoundationEIN 22-1905062 | Education | VA | $13,861,077Large | 81.14 |
| Marine Corps University FoundationEIN 54-1143646 | Education | VA | $2,054,228Small | 90.23 |
| Mario Lemieux FoundationEIN 25-1708231 | Health | PA | $1,249,212Small | 78.92 |
| Marion Polk Food ShareEIN 94-3034161 | Human Services | OR | $14,392,956Large | 91.31 |
| Mark Morris Dance GroupEIN 13-3577394 | Arts, Culture, Humanities | NY | $8,923,444Mid-sized | 91.94 |
| Mark Wahlberg Youth FoundationEIN 04-3567369 | Education | MA | $1,573,707Small | 92.22 |
| Mars Hill ProductionsEIN 76-0235320 | Religion | TX | $979,513Small | 83.98 |
| Martha O'Bryan CenterEIN 62-0477728 | Human Services | TN | $14,942,210Large | 89.19 |
| Martha's KitchenEIN 91-2091094 | Human Services | CA | $1,854,157Small | 91.51 |
| Martha's TableEIN 52-1186071 | Human Services | DC | $12,419,059Mid-sized | 97.13 |
| Martha's Village and KitchenEIN 33-0777892 | Human Services | CA | $3,578,914Mid-sized | 71.26 |
| Martha's Vineyard MuseumEIN 04-2160642 | Arts, Culture, Humanities | MA | $2,030,611Small | 73.37 |
| MarwenEIN 36-3523622 | Education | IL | $2,669,179Small | 86.93 |
| Mary's CenterEIN 52-1594116 | Human Services | DC | $46,327,345Large | 93.76 |
| Maryland Food BankEIN 52-1135690 | Human Services | MD | $68,947,210Large | 82.13 |
| Maryland Historical SocietyEIN 52-0403670 | Arts, Culture, Humanities | MD | $3,479,411Small | 84.20 |
| Maryland Science CenterEIN 52-0668166 | Arts, Culture, Humanities | MD | $8,419,673Mid-sized | 82.58 |
| Maryland Therapeutic RidingEIN 52-2035698 | Health | MD | $988,423Small | 80.56 |
| MasbiaEIN 20-1923521 | Human Services | NY | $1,581,255Small | 67.39 |
| Masonic Home for Children at OxfordEIN 56-0603924 | Human Services | NC | $5,835,714Mid-sized | 83.95 |
| Masonic Home of GeorgiaEIN 58-0140568 | Human Services | GA | $1,970,070Small | 87.50 |
| Masonic Homes of CaliforniaEIN 94-1156564 | Human Services | CA | $63,193,734Large | 91.49 |
| Masonic Medical Research LaboratoryEIN 13-5648611 | Health | NY | $3,253,665Small | 79.52 |
| Mass Mentoring PartnershipEIN 22-3207958 | Human Services | MA | $2,420,195Small | 87.97 |
| MASS MoCAEIN 04-3113688 | Arts, Culture, Humanities | MA | $14,296,459Large | 79.41 |
| Massachusetts Audubon SocietyEIN 04-2104702 | Environment | MA | $29,467,469Large | 95.33 |