| School | Roll number | County | Total (latest year) | Latest average class size | Largest class | Classes 30+ |
|---|---|---|---|---|---|---|
| St. Joseph's N.S. | 18797W | Offaly | 360 | 16.90 | 19 | 0 |
| SCOIL COLMAIN NAOFA | 17746A | Offaly | 322 | 23.38 | 32 | 2 |
| SHINCHILL N S | 17031F | Offaly | 286 | 22.83 | 30 | 2 |
| DAINGEAN N S | 16620T | Offaly | 261 | 22.64 | 30 | 2 |
| SCOIL MHUIRE | 18057F | Offaly | 249 | 16.43 | 24 | 0 |
| Tullamore Educate Together NS | 20189L | Offaly | 236 | 22.40 | 29 | 0 |
| ARDEN BOYS NS | 19713S | Offaly | 215 | 23.22 | 27 | 0 |
| BALLYKILMURRY N S | 15656M | Offaly | 199 | 22.62 | 25 | 0 |
| S N NAOMH CHOLUMCHILLE | 17508H | Offaly | 197 | 23.88 | 30 | 1 |
| S N SHEOSAIMH NAOFA | 17637S | Offaly | 193 | 22.62 | 29 | 0 |
| GAELSCOIL AN EISCIR RIADA | 19990V | Offaly | 185 | 23.12 | 26 | 0 |
| CHARLEVILLE N S | 10353P | Offaly | 173 | 23.00 | 27 | 0 |
| S N NAOMH PHILOMENA | 16928B | Offaly | 164 | 19.88 | 26 | 0 |
| S N Chartaigh Naofa | 20273A | Offaly | 147 | 16.71 | 27 | 0 |
| GEASHILL 1 N S | 09191I | Offaly | 126 | 18.67 | 27 | 0 |
| S N NAOMH BRIGHDE BUACH | 18524K | Offaly | 116 | 17.50 | 23 | 0 |
| S N SEOSAMH | 07191V | Offaly | 97 | 21.25 | 27 | 0 |
| ST COLMANS N S | 19354Q | Offaly | 97 | 24.25 | 28 | 0 |
| S N MHUIRE | 18795S | Offaly | 72 | 24.00 | 31 | 1 |
| SCOIL BHRIDE | 18690E | Offaly | 70 | 17.50 | 26 | 0 |