Riabhaigh Mac Riabhaigh ga  | Riabhach |
Riabhaigh Mhic Riabhaigh ga  | Riabhach |
| Riabhaigh Nic Riabhaigh ga | Riabhach |
| Riada Ó Riada ga | Riad |
| Riada Uí Riada ga | Riad |
| Riada Ní Riada ga | Riad |
| Riagáin Ó Riagáin ga | Riagán |
| Riagáin Uí Riagáin ga | Riagán |
| Riagáin Ní Riagáin ga | Riagán |
| Riain Ó Riain ga | Rian |
| Riain Uí Riain ga | Rian |
| Riain Ní Riain ga | Rian |
| Riallais Mac Riallais ga | Riallais |
| Riallais Mhic Riallais ga | Riallais |
| Riallais Nic Riallais ga | Riallais |
| Rice en | Maolchraoibhe |
| Richardson en | Risteard |
| Rickard en | Riocard |
| Ridire Mac an Ridire ga | Ridire |
| Ridire Mhic an Ridire ga | Ridire |
| Ridire Nic an Ridire ga | Ridire |
| Rigney en | Raigne |
| Ring en | Rinn |
| Rinn Ó Rinn ga | Rinn |
| Rinn Uí Rinn ga | Rinn |
| Rinn Ní Rinn ga | Rinn |
| Riocaird Mac Riocaird ga | Riocard |
| Riocaird Mhic Riocaird ga | Riocard |
| Riocaird Nic Riocaird ga | Riocard |
| Ríoghbhardáin Ó Ríoghbhardáin ga | Ríordán |
| Ríoghbhardáin Uí Ríoghbhardáin ga | Ríordán |
| Ríoghbhardáin Ní Ríoghbhardáin ga | Ríordán |
| Riordáin Ó Riordáin ga | Riordán |
| Riordáin Uí Riordáin ga | Riordán |
| Riordáin Ní Riordáin ga | Riordán |
| Ríordáin Ó Ríordáin ga | Ríordán |
| Ríordáin Uí Ríordáin ga | Ríordán |
| Ríordáin Ní Ríordáin ga | Ríordán |
| Riordan O'Riordan en | Ríordán |
| Riordan en | Ríordán |
| Riordan en | Riordán |
| Risteaird Mac Risteaird ga | Risteard |
| Risteaird Mhic Risteaird ga | Risteard |
| Risteaird Nic Risteaird ga | Risteard |
| Roache en | Róiste |
| Roarke O'Roarke en | Ruarc |
| Roberts en | Roibeard |
| Robinson en | Roibín |
| Roche en | Róiste |
| Rochford en | Rosfort |