The implied results are now calculated using the local election results for the wards which make up each old seat. This should be more accurate than the earlier implied results which assumed each constituency was homogeneous.
On that basis, only one seat "changes hands". This is the old seat of Caernarfon which mostly becomes the new seat of Arfon. Whereas Caernarfon was a strong PC seat, the new Arfon is a close PC-Lab marginal, with a Labour majority of 647 votes.
Full implied 2005 results for Wales are available.
| New seat | Primary component | Secondary component | ||
| Aberconwy | 67.3% of Conwy | 20.7% of Meirionnydd Nant Conwy | ||
| Alyn and Deeside | Unchanged | |||
| Clwyd South | 95.1% of Clwyd South | |||
| Clwyd West | 99.0% of Clwyd West | 2.4% of Clwyd South | ||
| Delyn | Unchanged | |||
| Vale of Clwyd | 100% of Vale of Clwyd | 1.0% of Clwyd West | ||
| Wrexham | Unchanged |
| New seat | Primary component | Secondary component | ||
| Carmarthen East and Dinefwr | 97.5% of Carmarthen East and Dinefwr | |||
| Carmarthen West and Pembrokeshire South | 98.9% of Carmarthen West and Pembrokeshire South | 2.5% of Carmarthen East and Dinefwr | ||
| Ceredigion | 99.3% of Ceredigion | |||
| Llanelli | Unchanged | |||
| Preseli Pembrokeshire | 100% of Preseli Pembrokeshire | 1.1% of Carmarthen West and Pembrokeshire South
0.7% of Ceredigion |
| New seat | Primary component | Secondary component | ||
| Arfon | 53.1% of Caernarfon | 32.7% of Conwy | ||
| Dwyfor Meirionnydd | 79.3% of Meirionnydd Nant Conwy | 46.9% of Caernarfon | ||
| Ynys Mon | Unchanged |
| New seat | Primary component | Secondary component | ||
| Blaenau Gwent | Unchanged | |||
| Bridgend | 91.0% of Bridgend | |||
| Caerphilly | 93.4% of Caerphilly | |||
| Cynon Valley | 100% of Cynon Valley | 6.1% of Pontypridd | ||
| Islwyn | 100% of Islwyn | 6.6% of Caerphilly | ||
| Merthyr Tydfil And Rhymney | Unchanged | |||
| Monmouth | Unchanged | |||
| Newport East | Unchanged | |||
| Newport West | Unchanged | |||
| Ogmore | 100% of Ogmore | 4.5% of Bridgend | ||
| Pontypridd | 86.0% of Pontypridd | |||
| Rhondda | Unchanged | |||
| Torfaen | Unchanged |
| New seat | Primary component | Secondary component | ||
| Brecon and Radnorshire | Unchanged | |||
| Montgomeryshire | 100% of Montgomeryshire | 2.5% of Clwyd South |
| New seat | Primary component | Secondary component | ||
| Cardiff Central | Unchanged | |||
| Cardiff North | Unchanged | |||
| Cardiff South and Penarth | 100% of Cardiff South and Penarth | 4.8% of Vale of Glamorgan | ||
| Cardiff West | 100% of Cardiff West | 7.9% of Pontypridd | ||
| Vale of Glamorgan | 95.2% of Vale of Glamorgan | 4.5% of Bridgend |
| New seat | Primary component | Secondary component | ||
| Aberavon | Unchanged | |||
| Gower | 100% of Gower | 0.0% of Neath | ||
| Neath | Unchanged | |||
| Swansea East | Unchanged | |||
| Swansea West | Unchanged |