| Pakefield High School146909 | Secondary | Good | 38.4% | 679 |
| Paddocks Primary School124565 | Primary | Good | 18.4% | 179 |
| Oulton Broad Primary School124676 | Primary | Outstanding | 19.8% | 378 |
| Otley Primary School124602 | Primary | Good | 17.6% | 51 |
| Orwell Park School124866 | Not applicable | — | — | 167 |
| Ormiston Sudbury Academy138506 | Secondary | Needs attention | 35.5% | 710 |
| Ormiston Endeavour Academy137674 | Secondary | Good | 31.5% | 793 |
| Ormiston Denes Academy139403 | Secondary | Good | 58.4% | 711 |
| Orford Church of England Primary School and Nursery150252 | Primary | Good | 32.4% | 34 |
| OneSchool Global UK Colchester Campus134480 | Not applicable | — | — | 120 |
| One Sixth Form College142283 | 16 plus | — | 0.0% | 2,404 |
| On Track Education Mildenhall127003 | Not applicable | — | — | 56 |
| Old Newton Church of England Primary School143070 | Primary | Good | 15.7% | 70 |
| Old Buckenham Hall School124873 | Not applicable | — | — | 199 |
| Occold Primary School146173 | Primary | Good | 13.2% | 53 |
| Oa - Suffolk142820 | Not applicable | Good | 50.0% | 2 |
| Norton Cevc Primary School124710 | Primary | Good | 12.3% | 203 |
| Northgate High School124840 | Secondary | Good | 19.5% | 1,750 |
| Northfield St Nicholas Primary Academy142016 | Primary | Good | 44.3% | 311 |
| Newmarket Academy140669 | Secondary | Good | 23.3% | 797 |
| New Skill Centre146332 | Not applicable | — | — | 70 |
| New Cangle Community Primary School124537 | Primary | Good | 16.7% | 210 |
| Ness Point School148425 | Not applicable | — | — | 30 |
| Nayland Primary School124543 | Primary | Good | 6.6% | 197 |
| Nacton Church of England Primary School142994 | Primary | Good | 10.0% | 100 |
| Murrayfield Primary - A Paradigm Academy143550 | Primary | Good | 45.8% | 400 |
| Moulton Church of England Voluntary Controlled Primary School124709 | Primary | Outstanding | 11.2% | 206 |
| Morland Church of England Primary School145851 | Primary | Good | 36.4% | 358 |
| Mildenhall College Academy139867 | Secondary | Good | 23.8% | 1,317 |
| Middleton Community Primary School143806 | Primary | Good | 43.8% | 16 |
| Mendlesham Primary School143361 | Primary | Good | 17.0% | 100 |
| Mendham Primary School143069 | Primary | Good | 33.3% | 57 |
| Melton Primary School124597 | Primary | Needs attention | 35.7% | 163 |
| Mellis Church of England Primary School143807 | Primary | Good | 4.1% | 147 |
| Martlesham Primary Academy142018 | Primary | Good | 25.6% | 125 |
| Long Melford Church of England Primary School143147 | Primary | Good | 20.9% | 207 |
| Leiston Primary School141554 | Primary | Requires Improvement | 34.4% | 383 |
| Learning Support, Western Area Education Office133238 | Not applicable | — | — | — |
| Learning Support, Southern Area Education Office133237 | Not applicable | — | — | — |
| Learning Support, Northern Area Education Office133239 | Not applicable | — | — | — |
| Lavenham Community Primary School124540 | Primary | Good | 21.9% | 114 |
| Laureate Community Academy142993 | Primary | Good | 13.4% | 239 |
| Langer Primary Academy138117 | Primary | Good | 45.8% | 144 |
| Lakenheath Community Primary School124539 | Primary | Good | 20.2% | 282 |
| Kyson Primary School152031 | Primary | Good | 20.3% | 380 |
| Kingsfleet Primary School124627 | Primary | Good | 20.0% | 185 |
| King Edward Vi Cevc School124856 | Secondary | Good | 21.9% | 1,189 |
| Kessingland Church of England Primary Academy141172 | Primary | Good | 50.3% | 198 |
| Kesgrave High School136969 | Secondary | Good | 15.3% | 1,875 |
| Kersey Church of England Primary School148846 | Primary | Good | 25.0% | 40 |