Grefkenstraat is een straat te Brunssum in de gemeente Brunssum en is gelegen in de Nederlandse provincie Limburg.
| Postcode | Huisnummers |
|---|---|
| 6443 EJ | 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49; |
| 6443 EK | 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32; |