All postcodes in SY23 9
| Postcode | Place | Type |
|---|---|---|
| SY23 9BQ | Aberystwyth | large user |
| SY23 9BW | Aberystwyth | large user |
| SY23 9BY | Aberystwyth | large user |
| SY23 9BZ | Aberystwyth | large user |
| SY23 9DG | Aberystwyth | large user |
| SY23 9DN | Aberystwyth | large user |
| SY23 9DP | Aberystwyth | large user |
| SY23 9DQ | Aberystwyth | large user |