| School | Roll number | County | Total (latest year) | Latest average class size | Largest class | Classes 30+ |
|---|---|---|---|---|---|---|
| GAELSCOIL ULTAIN | 19936P | Monaghan | 373 | 23.31 | 26 | 0 |
| URBLESHANNY N S | 16923O | Monaghan | 296 | 22.31 | 29 | 0 |
| SCOIL NAOMH DEAGHA | 19251G | Monaghan | 286 | 26.00 | 33 | 5 |
| SCOIL ROIS | 19857T | Monaghan | 260 | 26.00 | 32 | 3 |
| Bunscoil Louis Naofa | 15329U | Monaghan | 258 | 23.45 | 32 | 1 |
| NAOMH OLIVER PLUNKETT | 19469K | Monaghan | 255 | 25.22 | 34 | 1 |
| St Joseph's National School | 17099Q | Monaghan | 234 | 22.80 | 30 | 1 |
| ST MARYS BNS | 17150N | Monaghan | 229 | 22.56 | 31 | 1 |
| Scoil Éanna | 20174V | Monaghan | 228 | 25.33 | 33 | 3 |
| St Tiarnach's Primary School | 20120V | Monaghan | 217 | 22.22 | 30 | 1 |
| ST LOUIS INFANT SCHOOL | 18494E | Monaghan | 208 | 23.11 | 25 | 0 |
| SCOIL NAOIMH EANNA | 05501A | Monaghan | 203 | 25.38 | 30 | 1 |
| CORR A CHRAINN NATIONAL SCHOOL | 18028V | Monaghan | 202 | 24.50 | 31 | 2 |
| SCOIL NAOMH MHUIRE | 18539A | Monaghan | 202 | 23.00 | 27 | 0 |
| ST. LOUIS GIRLS NATIONAL SCHOOL | 00359V | Monaghan | 202 | 24.62 | 28 | 0 |
| Castleblayney Convent Infants National School | 16319W | Monaghan | 197 | 21.12 | 26 | 0 |
| Annyalla National School | 16842O | Monaghan | 195 | 24.38 | 28 | 0 |
| SCOIL MHUIRE BNS | 17686I | Monaghan | 183 | 24.43 | 33 | 1 |
| LATTON | 19434O | Monaghan | 161 | 26.83 | 30 | 1 |
| Edenmore N.S. | 20337A | Monaghan | 159 | 22.29 | 35 | 1 |
| Gaelscoil Lorgan | 20327U | Monaghan | 159 | 26.50 | 32 | 2 |
| Castleblayney Convent National School | 16202B | Monaghan | 155 | 24.00 | 33 | 2 |
| LISDOONAN N S | 15143G | Monaghan | 150 | 25.00 | 31 | 1 |
| SCOIL PHADRAIG | 19736H | Monaghan | 142 | 23.67 | 29 | 0 |
| THREEMILEHOUSE N S | 19162H | Monaghan | 141 | 20.50 | 24 | 0 |
| ST PATRICKS NS | 17735S | Monaghan | 140 | 23.33 | 25 | 0 |
| DOOHAMLET N S | 06117E | Monaghan | 134 | 20.50 | 25 | 0 |
| ST DYMPNAS NS | 19738L | Monaghan | 124 | 23.60 | 30 | 1 |
| KNOCKCONNON N S | 15654I | Monaghan | 118 | 23.60 | 30 | 1 |
| NAOMH MICHEAL | 15142E | Monaghan | 108 | 24.25 | 30 | 1 |
| SCOIL BRIDE | 19780K | Monaghan | 106 | 21.20 | 23 | 0 |
| S N CHOLMCILLE | 18820O | Monaghan | 103 | 25.75 | 30 | 1 |
| KILLEEVAN CENTRAL N S | 19364T | Monaghan | 101 | 25.25 | 29 | 0 |
| SCOIL MHUIRE | 09186P | Monaghan | 99 | 24.75 | 32 | 1 |
| CORCAGHAN N S | 16129R | Monaghan | 92 | 23.00 | 26 | 0 |
| SCOIL NAOMH PADRAIG | 18234B | Monaghan | 87 | 21.75 | 27 | 0 |
| SCOIL MHUIRE | 18401R | Monaghan | 86 | 21.50 | 27 | 0 |
| LATNAMARD N S | 16769H | Monaghan | 85 | 21.25 | 28 | 0 |
| MHUIRE GRANSLA | 18482U | Monaghan | 77 | 19.25 | 22 | 0 |
| SCOIL MHUIRE | 10429W | Monaghan | 76 | 19.00 | 23 | 0 |
| DRUMGOSSETT N S | 14071C | Monaghan | 75 | 18.75 | 23 | 0 |
| SCOIL BHRIGHDE | 18256L | Monaghan | 75 | 25.00 | 27 | 0 |
| DERAVOY NATIONAL SCHOOL | 00373P | Monaghan | 71 | 17.75 | 21 | 0 |
| SCOIL ENDA | 17126Q | Monaghan | 69 | 23.00 | 25 | 0 |
| SCOIL MHICHIL | 16954C | Monaghan | 60 | 20.00 | 24 | 0 |
| ST JOSEPHS N S | 20067U | Monaghan | 60 | 20.00 | 24 | 0 |
| ANNALITTEN N S | 13632L | Monaghan | 37 | 16.00 | 20 | 0 |
| St. Brigid's National School Aughnafarcon | 18023L | Monaghan | 37 | 18.50 | 28 | 0 |
| CORCREAGH N S | 13811L | Monaghan | 34 | 17.00 | 19 | 0 |
| ST PATRICKS N S | 19362P | Monaghan | 33 | 16.50 | 19 | 0 |
| S N BLAITHIN IOSA | 16968N | Monaghan | 27 | 13.50 | 14 | 0 |
| SCOIL PHADRAIG | 19036C | Monaghan | 23 | 11.50 | 14 | 0 |
| S N COMHGHALL | 17776J | Monaghan | 17 | 8.50 | 9 | 0 |