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