Before (end of 1976) (85 seats, Elections Centre)
Labour 62 · Plaid Cymru - The Party of Wales 10 · Other 8 · Conservative 3 · The Liberal Party 2
After (end of 1977) (85 seats, Elections Centre)
Labour 48 · Plaid Cymru - The Party of Wales 18 · Other 9 · Conservative 8 · The Liberal Party 2
Ward results
Aberdare No.1 Llwydcoed2 seats · turnout 45.1%
| J. Powell | Labour | 2,009 |
| M. Prowle | Labour | 1,925 |
| G. Edwards | Plaid Cymru - The Party of Wales | 1,917 |
| S. Edwards | Plaid Cymru - The Party of Wales | 1,741 |
| M. Winter | Independent | 285 |
Aberdare No.2 Blaengwawr1 seat · turnout 66.4%
| G. Owen | Plaid Cymru - The Party of Wales | 2,320 |
| H. Cole | Labour | 1,558 |
Aberdare No.3 Gladlys1 seat · turnout 43.8%
| V. Llywelyn | Labour | 989 |
| A. Skitt | Plaid Cymru - The Party of Wales | 753 |
Aberdare No.4 Town1 seat · turnout 47.0%
| P. Williams | Independent | 958 |
| W. Price | Labour | 681 |
Aberdare No.5 Aberaman1 seat · turnout 87.3%
| R. Reed | Labour | 1,836 ✓ |
| D. Barnett | Plaid Cymru - The Party of Wales | 1,281 |
Abertidwr & Senghenydd [caerphill1 seat · turnout 42.5%
| J. Davies | Residents | 1,650 ✓ |
| E. Wright | Labour | 563 |
Bedwas & Machen2 seats · turnout 54.2%
| R. Davies | Labour | 2,580 ✓ |
| C. Hobbs | Labour | 2,117 ✓ |
| A. Donaldson | LIB | 2,088 |
| T. Davies | Plaid Cymru - The Party of Wales | 1,129 |
| E. Haines | Conservative | 902 |
| E. Lewis | Plaid Cymru - The Party of Wales | 783 |
| I. Edwards | Independent | 542 |
Bedwellty Abertysswg1 seat · turnout 58.0%
| I. Evans | Plaid Cymru - The Party of Wales | 1,440 |
| S. Powell | Labour | 1,062 |
Bedwellty No.1 (Aberbargoed)1 seat · turnout 56.7%
| K. Szerard | Plaid Cymru - The Party of Wales | 908 |
| W. Forbes | Labour | 785 |
Bridgend2 seats · turnout 49.9%
| A. Parker | Conservative | 2,747 ✓ |
| W. Rutter | Conservative | 2,346 ✓ |
| A. Bowen | Labour | 1,616 |
| K. Morgan | Labour | 1,474 |
| E. King | RATE | 1,281 |
| G. Morris | RATE | 950 |
| D. Jones | Plaid Cymru - The Party of Wales | 491 |
| E. Lewis | Plaid Cymru - The Party of Wales | 467 |
Caerphilly No.11 seat · turnout 64.8%
| L. Lewis | Labour | 1,040 |
| A. Jewell | Plaid Cymru - The Party of Wales | 742 |
| E. Evans | Conservative | 257 |
Caerphilly No.2 Llanbradach1 seat · turnout 55.4%
| C. Mann | Plaid Cymru - The Party of Wales | 1,249 |
| E. White | Labour | 815 |
| E. Edwards | Conservative | 387 |
Caerphilly No.41 seat · turnout 48.9%
| L. Whittle | Plaid Cymru - The Party of Wales | 1,340 |
| B. Rowland | Labour | 1,331 |
| R. Lea | Conservative | 640 |
Caerphilly No.5 North1 seat · turnout 46.5%
| R. Jewell | Labour | 1,012 ✓ |
| A. Hallett | Plaid Cymru - The Party of Wales | 674 |
| V. Evans | RATE | 146 |
| B. Williams | Conservative | 146 |
Caerphilly No.6 South1 seat · turnout 52.8%
| H. Richards | Independent | 781 ✓ |
| G. Snell | Labour | 652 |
| A. Goodchild | RATE | 465 |
| M. Ryland | Independent | 443 |
Cardiff Rural1 seat · turnout 53.7%
| C. Richards | Labour | 701 ✓ |
| P. Enticott | Plaid Cymru - The Party of Wales | 622 |
| P. Dawkins | Conservative | 347 |
| A. Skelhorne | RATE | 260 |
Cowbridge Rural1 seat · turnout 47.5%
| J. David | Independent | 1,618 |
| J. Davies | Plaid Cymru - The Party of Wales | 966 |
Dowlais1 seat · turnout 55.0%
| T. Lewis | Labour | 1,245 |
| P. Jones | Plaid Cymru - The Party of Wales | 1,214 |
| D. Smith | Liberal Democrats | 140 |
Gelligaer No.11 seat · turnout 57.2%
| G. Howells | Plaid Cymru - The Party of Wales | 1,492 |
| B. Williams | Labour | 1,449 |
| W. Morgan | Conservative | 210 |
Gelligaer No.21 seat · turnout 54.9%
| J. Davies | Labour | 1,087 |
| G. Roberts | Plaid Cymru - The Party of Wales | 509 |
Gelligaer No.31 seat · turnout 52.3%
| J. Jones | Plaid Cymru - The Party of Wales | 1,710 |
| I. Jenkins | Labour | 1,490 |
| B. Newman | Conservative | 351 |
Gelligaer No.42 seats · turnout 47.9%
| A. Rogers | Labour | 2,803 |
| W. Bowen | Labour | 2,693 |
| A. Evans | Plaid Cymru - The Party of Wales | 1,533 |
| N. Turner | Plaid Cymru - The Party of Wales | 1,441 |
| C. Collins | Conservative | 550 |
| R. Owen | Conservative | 529 |
Llantrisant & Llantwifadre No.14 seats · turnout 41.9%
| K. Eason | Labour | 3,398 ✓ |
| T. John | RATE | 3,098 ✓ |
| L. Lodwig | Labour | 3,057 ✓ |
| A. Tyrrell | Labour | 2,801 ✓ |
| N. James | Labour | 2,747 |
| R. Bunnage | Conservative | 2,636 |
| D. Pearse | Conservative | 2,594 |
| D. Brown | RATE | 2,446 |
| T. Jones | Plaid Cymru - The Party of Wales | 2,332 |
| T. Phillips | Plaid Cymru - The Party of Wales | 2,252 |
| D. Morris | Plaid Cymru - The Party of Wales | 2,130 |
| R. Kennard | Plaid Cymru - The Party of Wales | 2,083 |
| R. Verallo | LIB | 884 |
Llantrisant & Llantwit Fardre No.2 seats · turnout 46.1%
| D. McDonald | Labour | 2,867 |
| J. Thomas | Labour | 2,167 |
| E. Brinson | Independent | 1,357 |
| D. Davies | Plaid Cymru - The Party of Wales | 1,305 |
| J. Jones | Plaid Cymru - The Party of Wales | 1,199 |
| A. Farnworth | Conservative | 368 |
Maesteg No.11 seat · turnout 46.8%
| V. Hart | Labour | 2,023 |
| D. Lewis | Plaid Cymru - The Party of Wales | 678 |
| M. Rixon | Conservative | 203 |
Maesteg No.21 seat · turnout 54.3%
| J. Gibbs | LIB | 1,365 |
| W. Hayes | Labour | 758 |
| K. Rowe | Conservative | 172 |
Maesteg No.31 seat · turnout 49.8%
| W. Venner | Labour | 1,428 |
| T. Pearson | Plaid Cymru - The Party of Wales | 720 |
| G. Jones | Conservative | 378 |
Merthyr Cyfarthfa1 seat · turnout 54.6%
| M. Phillips | Plaid Cymru - The Party of Wales | 1,474 |
| D. Jones | Labour | 1,083 |
| D. Williams | LIB | 179 |
Merthyr No.61 seat · turnout 69.1%
| E. Griffiths | Plaid Cymru - The Party of Wales | 1,614 |
| B. Richards | Labour | 1,192 |
| R. Evans | COMM | 106 |
Merthyr No.71 seat · turnout 71.9%
| T. O'Brien | Labour | 1,344 |
| J. Gough | Plaid Cymru - The Party of Wales | 980 |
Merthyr Park2 seats · turnout 48.2%
| J. Burns | Labour | 1,956 ✓ |
| G. Foster | Plaid Cymru - The Party of Wales | 1,840 ✓ |
| G. Williams | Labour | 1,584 |
| C. Mathews | Plaid Cymru - The Party of Wales | 1,521 |
| C. Thomas | Conservative | 620 |
| A. Jones | COMM | 539 |
| G. Cooper | LIB | 288 |
| C. Bennett | COMM | 161 |
| D. Bettell-Higgins | Liberal Democrats | 152 |
Merthyr Town1 seat · turnout 57.7%
| T. Davies | Labour | 1,277 ✓ |
| L. Smith | Plaid Cymru - The Party of Wales | 813 |
| D. Davies | Conservative | 582 |
| T. Roberts | COMM | 112 |
| O. Bettell-Higgins | Liberal Democrats | 35 |
Mountain Ash No.11 seat · turnout 60.5%
| T. Davies | Labour | 1,662 |
| C. Jones | Plaid Cymru - The Party of Wales | 1,086 |
| A. Williams | COMM | 974 |
Mountain Ash No.21 seat · turnout 49.6%
| N. Thomas | Plaid Cymru - The Party of Wales | 1,066 |
| P. Brocklebank | Independent | 877 |
| F. Brooks | Plaid Cymru - The Party of Wales | 789 |
Mountain Ash No.32 seats · turnout 43.1%
| S. Lloyd | Labour | 1,940 |
| R. Humphreys | Plaid Cymru - The Party of Wales | 1,797 |
| G. Owen | Plaid Cymru - The Party of Wales | 1,736 |
| H. Evans | Labour | 1,734 |
Ogmore & Garw No.11 seat · turnout 70.1%
| D. Mordecai | RATE | 1,263 |
| M. David | Labour | 948 |
| G. Jones | Plaid Cymru - The Party of Wales | 148 |
Ogmore & Garw No.22 seats · turnout 47.9%
| T. Price | Labour | 2,476 |
| E. Merriman | Plaid Cymru - The Party of Wales | 2,428 |
| A. Lock | Labour | 2,364 |
| J. Jones | Plaid Cymru - The Party of Wales | 1,590 |
| J. Fenwick | Conservative | 569 |
| M. Eade | Conservative | 487 |
Penybont No.11 seat · turnout 51.6%
| L. Walters | Conservative | 1,081 ✓ |
| E. Mayball | Labour | 1,002 |
| I. Evans | RATE | 514 |
| P. Tomlin | Plaid Cymru - The Party of Wales | 227 |
Penybont No.21 seat · turnout 55.1%
| W. Board | Conservative | 1,064 ✓ |
| D. Thomas | Independent | 783 |
| S. Clark | LIB | 375 |
| D. Davies | Independent | 149 |
Penybont No.31 seat · turnout 45.8%
| J. Spurgeon | Conservative | 1,195 |
| A. Cattle | Labour | 1,186 |
| D. Williams | Plaid Cymru - The Party of Wales | 470 |
Penybont No.41 seat · turnout 47.2%
| D. Unwin | Conservative | 1,253 ✓ |
| G. Stevens | Labour | 755 |
| A. Elliott | RATE | 651 |
| S. Thomas | Plaid Cymru - The Party of Wales | 373 |
Penybont No.52 seats · turnout 53.7%
| E. Davies | Labour | 2,949 ✓ |
| M. Jones | Labour | 2,911 ✓ |
| V. Morgan-Thornton | Plaid Cymru - The Party of Wales | 1,598 |
| R. Lewis | Plaid Cymru - The Party of Wales | 1,338 |
| P. Davis | Conservative | 1,160 |
| P. Rixon | Conservative | 984 |
| A. Gordon-Cranmer | RATE | 591 |
Penybont No.62 seats · turnout 51.7%
| P. Squire | Labour | 1,994 |
| W. Barnett | Independent | 1,637 |
| Walter G. | Labour | 1,562 |
| M. Kennedy | Independent | 1,263 |
| G. Charles | Plaid Cymru - The Party of Wales | 743 |
| D. Jones | Plaid Cymru - The Party of Wales | 649 |
Penydarren1 seat · turnout 52.9%
| T. Mahoney | Labour | 1,500 |
| J. Price | Plaid Cymru - The Party of Wales | 823 |
| J. Lewis | LIB | 170 |
Pontypridd No.11 seat · turnout 54.2%
| W. Williams | Labour | 842 ✓ |
| S. Holcombe | Plaid Cymru - The Party of Wales | 743 |
| K. James | Independent | 411 |
| M. Farnworth | Conservative | 147 |
Pontypridd No.2 Town1 seat · turnout 53.7%
| W. Jones | Labour | 791 ✓ |
| S. Goodwin | Plaid Cymru - The Party of Wales | 704 |
| B. Murphy | LIB | 667 |
| M. Davis | Conservative | 207 |
Pontypridd No.31 seat · turnout 58.6%
| E. Peck | Labour | 1,141 |
| J. Bunnage | Conservative | 125 |
Pontypridd No.3 Clifynydd1 seat · turnout 67.5%
| P. Williams | Plaid Cymru - The Party of Wales | 1,480 |
| J. Knox | Conservative | 1,423 |
| G. Derbyshire | Labour | 700 |
Pontypridd No.4 Trallwn1 seat · turnout 62.9%
| M. Murphy | LIB | 990 ✓ |
| S. Cody | Plaid Cymru - The Party of Wales | 458 |
| R. Jones | Labour | 393 |
| Simon Schofield | Conservative | 150 |
Pontypridd No.5 Rhydyfelin1 seat · turnout 39.2%
| J. Davies | Labour | 1,103 ✓ |
| K. Williams | Independent | 869 |
| C. Holloway | Plaid Cymru - The Party of Wales | 490 |
| J. Beynon | Conservative | 251 |
Pontypridd No.6 Treforest & Graig1 seat · turnout 50.3%
| H. Weston | Labour | 1,180 ✓ |
| R. Mathews | LIB | 542 |
| E. Henly | Plaid Cymru - The Party of Wales | 522 |
| L. Jarman | Conservative | 406 |
Porthcawl No.11 seat · turnout 48.1%
| P. Hubbard-Miles | Conservative | 1,959 ✓ |
| C. Smart | RATE | 569 |
| D. Wilcox | Labour | 563 |
| W. Thomas | Plaid Cymru - The Party of Wales | 257 |
Porthcawl No.21 seat · turnout 49.4%
| H. Eastment | Conservative | 1,312 |
| G. McBride | Labour | 962 |
| R. Fattorini | Plaid Cymru - The Party of Wales | 249 |
Rhondda No.1 Treherbert2 seats · turnout 42.0%
| A. True | COMM | 2,143 |
| G. Williams | Labour | 1,694 |
| H. Elliott | Labour | 1,293 |
Rhondda No.10 Tylerstown1 seat · turnout 48.3%
| D. Morgan | Labour | 1,157 |
| B. Williams | RATE | 868 |
| A. Lewis | Plaid Cymru - The Party of Wales | 758 |
Rhondda No.11 Ferndale2 seats · turnout 60.8%
| G. James | Plaid Cymru - The Party of Wales | 2,306 |
| E. Hughes | Independent | 1,716 |
| J. Evans | COMM | 1,375 |
| L. Jones | Labour | 1,317 |
| L. Griffiths | Labour | 1,225 |
| T. Humphreys | Plaid Cymru - The Party of Wales | 996 |
Rhondda No.2 Treorchy2 seats · turnout 56.4%
| G. Rees | Labour | 2,007 |
| H. Jones | Labour | 1,988 |
| P. Davies | Plaid Cymru - The Party of Wales | 1,496 |
| R. Davies | Plaid Cymru - The Party of Wales | 1,455 |
| Sams J. | Independent | 385 |
Rhondda No.3 Pentre1 seat · turnout 59.2%
| E. Jenkins | Labour | 1,361 ✓ |
| M. John | Plaid Cymru - The Party of Wales | 582 |
| D. Gillespie | Conservative | 356 |
| R. Betteney | Independent | 311 |
Rhondda No.4 Ystrad1 seat · turnout 52.8%
| D. Thomas | Labour | 1,397 |
| D. Jones | Plaid Cymru - The Party of Wales | 809 |
| A. Price | COMM | 426 |
Rhondda No.51 seat · turnout 61.5%
| D. Morgan | Plaid Cymru - The Party of Wales | 1,455 |
| T. Parry | Labour | 1,397 |
| A. Speake | Conservative | 567 |
Rhondda No.61 seat · turnout 56.0%
| C. Winter | Labour | 1,463 |
| R. Leyshon | Conservative | 1,416 |
| A. Jones | Plaid Cymru - The Party of Wales | 421 |
Rhondda No.7 Penygraig1 seat · turnout 47.0%
| C. Richards | Labour | 1,262 |
| C. Lindsey | Conservative | 730 |
| G. Jones | Plaid Cymru - The Party of Wales | 608 |
Rhondda No.8 Porth2 seats · turnout 43.8%
| A. Ellis | Labour | 1,828 |
| L. Rees | Labour | 1,693 |
| T. Jones | RATE | 1,507 |
| E. Fitsall | RATE | 1,454 |
| R. Tomkinson | Conservative | 650 |
Rhondda No.91 seat · turnout 61.6%
| D. May | RATE | 1,135 |
| S. McElistrim | Labour | 1,122 |
| M. Fisk | Plaid Cymru - The Party of Wales | 560 |
Rhymney1 seat · turnout 51.5%
| J. Williams | Labour | 1,646 |
| A. Lippiett | Plaid Cymru - The Party of Wales | 644 |
Treharris1 seat · turnout 51.2%
| T. Richards | Labour | 1,477 |
| M. Moran | Plaid Cymru - The Party of Wales | 711 |
Vaynor & Penderyn1 seat · turnout 62.5%
| C. Harris | Plaid Cymru - The Party of Wales | 991 |
| M. Byrne | Labour | 905 |
Vaynor & Penderyn No.21 seat · turnout 64.5%
| T. Smith | Labour | 729 ✓ |
| P. Williams | Plaid Cymru - The Party of Wales | 606 |
| A. Hodges | Conservative | 257 |
| A. Jenkins | LIB | 121 |
