| Σ | # | Presentation | Description | Related |
| 8 | 450 | ⟨a, b | bab=aa, bbb=1⟩ | Finite non-commutative monoid with 27 elements | 27 iso |
| 8 | 752 | ⟨a, b | aaa=1, babb=a⟩ | Finite non-Abelian group with 27 elements | 58 iso, 1 anti-iso |
| 9 | 1695 | ⟨a, b | bab=aa, bbb=b⟩ | Finite non-commutative monoid with 27 elements | 1 iso |
| 10 | 5300 | ⟨a, b | aaa=aa, aba=bb⟩ | Finite non-commutative monoid with 27 elements | |
| 11 | 15514 | ⟨a, b | aaa=bb, aabaa=b⟩ | Finite non-commutative monoid with 27 elements | |
| 11 | 18739 | ⟨a, b | aaa=a, abbbbb=b⟩ | Finite non-commutative monoid with 27 elements | |