The 9 rare native British and Irish species are restricted to very few sites and in some cases to very few individuals
| SCIENTIFIC NAME | ENGLISH NAME | FAMILY | IMAGE |
| Anogramma leptophylla (L.) Link | Jersey Fern | Adiantaceae |  |
| Asplenium onopteris L. | Western Spleenwort | Aspleniaceae |  |
| Cystopteris diaphana (Bory) Blasdell | Wintergreen Bladder Fern | Woodsiaceae |  |
| C. dickeana Sim | Dickie’s Bladder Fern |  |
|
| C. montana (Lam.) Desv. | Mountain Bladder Fern |  |
|
| Ophioglossum azoricum C. Presl. | Small Adder's Tongue | Ophioglossaceae |  |
| O. lusitanicum L. | Least Adder's Tongue |  |
|
| Trichomanes speciosum Willd. | Killarney Fern | Hymenophyllaceae |  |
| Woodsia alpina (Bolton) S.F.Gray | Alpine Woodsia | Woodsiaceae |  |
| W. ilvensis (L.) R.Br. | Oblong Woodsia |  |
The 6 scarce native species are absent from most of Britain and Ireland, and confined to a limited habitat range, but may be locally common within their restricted distribution
| SCIENTIFIC NAME | ENGLISH NAME | FAMILY | IMAGE |
| Adiantum capillus-veneris L. | Maidenhair Fern | Adiantaceae |  |
| Asplenium obovatum Viv. subspecies lanceolatum (Huds.) P.Silva (= A. billotii) | Lanceolate Spleenwort | Aspleniaceae | |
| Athyrium distentifolium Tausch | Alpine Lady Fern | Woodsiaceae |  |
| Dryopteris cristata (L.) A.Gray | Fen Buckler Fern | Dryopteridaceae |  |
| D. submontana (Fras.-Jenkins & Jermy) Fras.-Jenkins | Rigid Buckler Fern |  |
|
| Pteridium pinetorum C.N.Page & R.R.Mill. | Northern Bracken | Dennstaedtiaceae |  |
