| 26 | Bedford Modern School | 1,252 pupils | Independent · Day · 6th | Bedford, East of England | — ISI · Good |
| 27 | Norwich School | 1,170 pupils | Independent · Day · 6th | Norwich, East of England | — |
| 28 | Abbey College Cambridge | 428 pupils | Independent · Boarding · 6th | Cambridgeshire, East of England | — ISI · Good |
| 29 | The Peterborough School | 514 pupils | Independent · Day · 6th | Peterborough, East of England | — ISI · Good |
| 30 | Thetford Grammar School | 202 pupils | Independent · Boarding · 6th | Unknown, East of England | — ISI · Good |
| 31 | Cambridge Arts and Sciences (CATS and CSVPA) | 534 pupils | Independent · Boarding · 6th | Cambridge, East of England | — ISI · Good |
| 32 | Sherrardswood School | 467 pupils | Independent · Day · 6th | Welwyn, East of England | — ISI · Good |
| 33 | Ipswich High School | 534 pupils | Independent · Boarding · 6th | Unknown, East of England | — ISI · Good |
| 34 | Finborough School | 680 pupils | Independent · Boarding · 6th | Stowmarket, East of England | — ISI · Good |
| 35 | Framlingham College | 557 pupils | Independent · Boarding · 6th | Woodbridge, East of England | — |
| 36 | Tring Park School for the Performing Arts | 333 pupils | Independent · Boarding · 6th | Tring, East of England | — ISI · Good |
| 37 | Stoke College | 104 pupils | Independent · Boarding · 6th | Sudbury, East of England | — ISI · Good |
| 38 | The Purcell School | 195 pupils | Independent · Boarding · 6th | Unknown, East of England | — ISI · Good |
| 39 | Saint Felix School | 244 pupils | Independent · Boarding · 6th | Southwold, East of England | — ISI · Good |
| 40 | Bedford Greenacre Independent School | 733 pupils | Independent · Day · 6th | Bedford, East of England | — ISI · Good |
| 41 | Gosfield School | 368 pupils | Independent · Day · 6th | Unknown, East of England | — ISI · Good |
| 42 | OneSchool Global UK Colchester Campus | 131 pupils | Independent · Day · 6th | Colchester, East of England | — ISI · Good |
| 43 | St Joseph's College | 577 pupils | Independent · Boarding · 6th | Ipswich, East of England | — |
| 44 | Thorpe Hall School | 552 pupils | Independent · Day | Unknown, East of England | — ISI · Good |
| 45 | Colchester Prep & High School | 281 pupils | Independent · Day | Colchester, East of England | — ISI · Good |
| 46 | Mander Portman Woodward | 159 pupils | Independent · Day · 6th | Cambridge, East of England | — |
| 47 | Sancton Wood School | 391 pupils | Independent · Day | Unknown, East of England | — ISI · Good |
| 48 | Holmwood House School | 392 pupils | Independent · Boarding | Colchester, East of England | — ISI · Excellent |
| 49 | Stanborough Secondary School | 70 pupils | Independent · Day · 6th | Watford, East of England | — ISI · Good |
| 50 | St. Andrew's College Cambridge | 151 pupils | Independent · Boarding · 6th | Cambridge, East of England | — |