Llanrhystud Population 1801-1971
| Year | Haminiog | Male | Female | Mefenydd | Male | Female | Total |
| 1801 | – | – | – | – | – | – | 1148 |
| 1811 | 575 | – | – | 655 | – | – | 1230 |
| 1821 | 615 | – | – | 720 | – | – | 1335 |
| 1831 | 785 | – | – | 740 | – | – | 1525 |
| 1841 | 886 | 410 | 476 | 722 | 363 | 359 | 1608 |
| 1851 | 863 | 412 | 415 | 653 | 300 | 353 | 1516 |
| 1861 | 895 | 419 | 476 | 638 | 297 | 341 | 1533 |
| 1871 | 935 | 443 | 492 | 628 | 294 | 334 | 1563 |
| 1881 | 792 | 359 | 433 | 585 | 270 | 315 | 1377 |
| 1891 | 698 | 328 | 370 | 463 | 216 | 247 | 1161 |
| 1901 | 634 | 299 | 325 | 417 | 202 | 215 | 1051 |
| 1911 | 587 | 286 | 301 | 432 | 219 | 213 | 1019 |
| 1921 | 554 | 281 | 273 | 382 | 184 | 198 | 936 |
| 1931 | 507 | 259 | 248 | 299 | 141 | 158 | 806 |
| 1941 | – | – | – | – | – | – | – |
| 1951 | 479 | 251 | 228 | 324 | 168 | 156 | 803 |
| 1961 | 457 | 226 | 231 | 250 | 125 | 125 | 707 |
| 1971 | 453 | 228 | 281 | 233 | 122 | 111 | 686 |