Before (end of 1978)
Not known.
After (end of 1979)
Not known.
Ward results
Ferndale3 seats · turnout 69.8%
| G. James | Plaid Cymru - The Party of Wales | 2,727 |
| K. Rees | Labour | 2,682 |
| Linda Jones-Bulman | Labour | 2,598 |
| P. Davies | Labour | 2,311 |
| R. Morris | Independent | 2,085 |
| J. Evans | COMM | 2,006 |
| T. Humphreys | Plaid Cymru - The Party of Wales | 1,058 |
Llwynpia3 seats · turnout 57.1%
| T. Jones | Labour | 2,853 |
| E. Brown | Labour | 2,835 |
| R. Ashman | Labour | 2,643 |
| D. Morgan | Plaid Cymru - The Party of Wales | 1,147 |
Pentre3 seats · turnout 63.7%
| A. Davies | Labour | 2,345 |
| B. McGrath | Labour | 2,297 |
| D Lewis | Labour | 1,846 |
| M. Powell | Plaid Cymru - The Party of Wales | 1,247 |
| P. Roberts | Conservative | 791 |
Penygraig3 seats · turnout 59.2%
| D. Jones | Labour | 2,417 |
| A. Powell | COMM | 2,324 |
| H. Lawless | Labour | 1,655 |
| B. Rowland | Labour | 1,523 |
| G. Jones | Plaid Cymru - The Party of Wales | 996 |
| C. Lindsey | Conservative | 886 |
Porth3 seats
| T. Rees | RATE | 3,077 |
| R. Dentus | RATE | 2,995 |
| D. Davies | Labour | 2,927 |
| T. Matthews | RATE | 2,719 |
| G. Hughes | Labour | 2,466 |
| V. Lewis | Labour | 2,255 |
| J. Bevan | Plaid Cymru - The Party of Wales | 867 |
Trealaw3 seats · turnout 63.0%
| D Morgan | Labour | 2,522 |
| E. Hopkins | Labour | 2,471 |
| M. Williams | Labour | 2,292 |
| P. Leyshon | Conservative | 1,687 |
| R. Betteney | Independent | 1,369 |
| C. Pugh | Plaid Cymru - The Party of Wales | 840 |
Treherbert3 seats · turnout 64.9%
| K. Morgan | Labour | 3,550 |
| G. Rees | Labour | 3,292 |
| E. Evas | Labour | 2,789 |
| G. True | COMM | 2,252 |
Treorchy3 seats · turnout 72.2%
| E. Salathiel | Labour | 3,595 |
| A. Boxall | Labour | 3,506 |
| H. Blight | Labour | 3,127 |
| H. Davies | Plaid Cymru - The Party of Wales | 1,596 |
| C. Davies | Plaid Cymru - The Party of Wales | 1,429 |
| R. Steffan Ap | Plaid Cymru - The Party of Wales | 859 |
Tylerstown3 seats · turnout 64.3%
| M. Chard | RATE | 2,268 |
| M. Collins | Labour | 2,186 |
| J. Bevan | Labour | 1,898 |
| P. Thomas | RATE | 1,454 |
| I. Stokes | Labour | 1,364 |
| M. Perry | RATE | 1,182 |
| T. Lewis | Plaid Cymru - The Party of Wales | 634 |
| C. Gardiner | ACTC | 193 |
