Votes cast in the Mid and West Wales region. These votes are used to apportion additional members to parties unrepresented in the constituency vote.
| Labour | 61,733 | 25.9% | +8.3% | 2 | ||
| Plaid Cymru | 65,450 | 27.5% | +3.7% | 1 | ||
| Liberal Democrat | 16,181 | 6.8% | -3.1% | 1 | ||
| Conservative | 63,827 | 26.8% | +8.1% | 0 | ||
| Green | 10,545 | 4.4% | +0.9% | 0 | ||
| Abolish the Welsh Assembly | 8,073 | 3.4% | -1.1% | 0 | ||
| UKIP | 3,731 | 1.6% | -8.9% | 0 | ||
| Reform UK | 2,582 | 1.1% | +1.1% | 0 | ||
| Propel | 1,428 | 0.6% | +0.6% | 0 | ||
| Christian | 1,366 | 0.6% | +0.6% | 0 | ||
| Gwlad | 1,303 | 0.5% | +0.5% | 0 | ||
| Freedom Alliance | 1,181 | 0.5% | +0.5% | 0 | ||
| Communist | 589 | 0.2% | +0.2% | 0 | ||
| TUSC | 257 | 0.1% | +0.1% | 0 |
View the 8 seats elected by first-past-the-post in Mid and West Wales in 2021.
| Brecon and Radnorshire | Con gain from LD | ||
| Carmarthen East and Dinefwr | PC hold | ||
| Carmarthen West and South Pembrokeshire | Con hold | ||
| Ceredigion | PC hold | ||
| Dwyfor Meirionnydd | PC hold | ||
| Llanelli | Lab hold | ||
| Montgomeryshire | Con hold | ||
| Preseli Pembrokeshire | Con hold |