| School | Roll number | County | Total (latest year) | Latest average class size | Largest class | Classes 30+ |
|---|---|---|---|---|---|---|
| OUR LADY OF MERCY N S | 19985F | Sligo | 449 | 17.96 | 22 | 0 |
| S N URSULA | 18979F | Sligo | 439 | 24.06 | 29 | 0 |
| CARRAROE N S | 14636B | Sligo | 389 | 24.31 | 28 | 0 |
| SCOIL EOIN NAOFA | 19974A | Sligo | 289 | 17.80 | 25 | 0 |
| S N MOLAOISE | 18575E | Sligo | 274 | 24.45 | 32 | 2 |
| SCOIL ASICUS | 15004P | Sligo | 252 | 25.20 | 30 | 2 |
| RANSBORO NEW CENTRAL | 19635B | Sligo | 247 | 23.50 | 32 | 2 |
| RATHCORMACK N S | 19408N | Sligo | 244 | 24.40 | 30 | 1 |
| SCOIL MHUIRE AGUS IOSAF | 20122C | Sligo | 241 | 23.50 | 29 | 0 |
| S N EOIN NAOFA | 17838F | Sligo | 226 | 25.11 | 31 | 2 |
| SCOIL MHUIRE GAN SMAL | 19964U | Sligo | 215 | 23.89 | 32 | 1 |
| Carbury National School | 19495L | Sligo | 210 | 26.25 | 30 | 1 |
| Gaelscoil Chnoc na Re | 20044I | Sligo | 208 | 26.00 | 30 | 1 |
| ST EDWARDS N S | 17277O | Sligo | 207 | 18.27 | 21 | 0 |
| HOLY FAMILY SCHOOL | 20019J | Sligo | 192 | 24.00 | 30 | 1 |
| ST PATRICKS NS | 19942K | Sligo | 182 | 26.00 | 32 | 2 |
| ST BRENDANS NS | 19826I | Sligo | 177 | 23.57 | 31 | 1 |
| ROCKFIELD N S | 15378K | Sligo | 174 | 24.86 | 33 | 1 |
| ENNISCRONE N S | 13940W | Sligo | 137 | 27.40 | 30 | 1 |
| S N Realt na Mara | 17641J | Sligo | 117 | 23.40 | 29 | 0 |
| CARN N S | 12537M | Sligo | 116 | 23.20 | 26 | 0 |
| CORBALLA N S | 12171T | Sligo | 115 | 23.00 | 32 | 2 |
| KILGLASS N S | 15571E | Sligo | 114 | 22.80 | 27 | 0 |
| SOOEY N S | 18053U | Sligo | 112 | 22.40 | 27 | 0 |
| ARDKEERIN N S | 15217J | Sligo | 111 | 22.20 | 30 | 1 |
| CLOONACOOL N S | 04802J | Sligo | 103 | 25.75 | 31 | 1 |
| S N MUIRE GAN SMAL | 18029A | Sligo | 103 | 20.60 | 27 | 0 |
| MOYLOUGH N S | 13831R | Sligo | 100 | 25.00 | 30 | 1 |
| S N PAIRC ARD | 18715R | Sligo | 99 | 24.75 | 27 | 0 |
| S.N. Naomh Ailbhe | 20575Q | Sligo | 97 | 24.25 | 28 | 0 |
| CLIFFONEY N S | 16136O | Sligo | 96 | 24.00 | 31 | 1 |
| DROMORE WEST CENTRAL | 19688W | Sligo | 90 | 22.50 | 24 | 0 |
| BALLINTOGHER N S | 02013S | Sligo | 87 | 21.75 | 25 | 0 |
| SCOIL CROI NAOFA | 20113B | Sligo | 81 | 20.25 | 26 | 0 |
| SCOIL NAOMH AODAIN | 19392B | Sligo | 79 | 19.75 | 25 | 0 |
| S N NAITHI NAOFA | 04487E | Sligo | 77 | 19.25 | 28 | 0 |
| SN MUIRE GAN SMAL | 19389M | Sligo | 76 | 19.00 | 23 | 0 |
| S N PADRAIG NAOFA | 17021C | Sligo | 75 | 25.00 | 28 | 0 |
| ST PAULS NS COLLOONEY | 19416M | Sligo | 75 | 18.75 | 23 | 0 |
| S N CUL FADA | 18298E | Sligo | 73 | 18.25 | 23 | 0 |
| RATHLEE N S | 16492N | Sligo | 68 | 17.00 | 22 | 0 |
| S N LISSARA NAOFA | 17774F | Sligo | 66 | 22.00 | 26 | 0 |
| S N CLOCHOG | 18543O | Sligo | 61 | 20.33 | 22 | 0 |
| S N CNOC MIONNA | 18334F | Sligo | 52 | 17.33 | 20 | 0 |
| SLIGO PROJECT SCHOOL | 19910U | Sligo | 52 | 17.33 | 18 | 0 |
| S N NAOMH MHUIRE | 15342M | Sligo | 47 | 15.67 | 18 | 0 |
| KILROSS N S | 16044J | Sligo | 42 | 21.00 | 24 | 0 |
| Our Lady's National School | 20385L | Sligo | 40 | 7.33 | 10 | 0 |
| S N RONAIN NAOFA | 12767G | Sligo | 37 | 18.50 | 22 | 0 |
| OWENBEG N S | 03924S | Sligo | 36 | 15.50 | 18 | 0 |
| S N BHRIDE | 17725P | Sligo | 35 | 17.50 | 18 | 0 |
| CASTLEROCK N S | 13242V | Sligo | 31 | 15.50 | 19 | 0 |
| STOKANE NS | 14051T | Sligo | 30 | 15.00 | 15 | 0 |
| Taunagh National School | 13196R | Sligo | 30 | 15.00 | 16 | 0 |
| S N BAILE AN LUIG | 17599N | Sligo | 29 | 14.50 | 15 | 0 |
| S N NAOMH IOSEF | 18592E | Sligo | 29 | 14.50 | 22 | 0 |
| S N MUIRE GAN SMAL | 18580U | Sligo | 24 | 12.00 | 15 | 0 |
| KILLEENDUFF N S | 09691F | Sligo | 20 | 10.00 | 11 | 0 |
| KILLAVILLE N S | 15431L | Sligo | 19 | 9.50 | 11 | 0 |
| S N AODAIN | 18366S | Sligo | 16 | 8.00 | 11 | 0 |
| S N MHUIRE | 15337T | Sligo | 15 | 7.50 | 10 | 0 |
| LEAFFONEY N S | 15496Q | Sligo | 1 | 1.00 | 1 | 0 |