Colwyn may refer to:

• Colwyn Bay – town in north Wales
  • Bay of Colwyn Town Council – town council in north Wales
• Colwyn (district) – former district and borough in north Wales
  • Colwyn Borough Council – former council in north Wales
• Old Colwyn (formerly called Colwyn) – village in north Wales
• Aberconwy and Colwyn, now Conwy County Borough – county borough in Wales
• Afon Colwyn (River Colwyn) – river in north Wales
• Rhos Bay (also known as Colwyn Bay) – Bay in north Wales
• Colwyn Castle – castle in north Wales
• Colwyn (electoral ward) – electoral district in north Wales
• Colwyn Rural District – former rural district in mid Wales

• Baron Colwyn – peerage title in the United Kingdom
• Colwyn committee – Northern Ireland committee
• Colwyn, Pennsylvania – borough in Pennsylvania, United States