2003 in Wales

Incumbents

August - National Eisteddfod of Wales held at Meifod.
October 12 - The Friends of the Leinster hold a service at Holyhead to commemorate the 85th anniversary of the sinking of RMS Leinster by a German U-boat.
November - Michael Howard becomes leader of the Conservative Party.
December - Dafydd Wigley is appointed Pro-Chancellor of the University of Wales.
The former Brain's Old Brewery site in Cardiff is redeveloped into the 85,000 sq ft "Old Brewery Quarter".
Veteran Cardiff politician Stefan Terlezki goes to the European Parliament to press the case for eventual Ukrainian membership of the European Union.
In Channel 4's 100 Worst Britons poll (which included only living people), the following entries had Welsh connections:
- H from Steps - 8
- Charlotte Church - 21
- Charles, Prince of Wales - 24
- Catherine Zeta-Jones - 39
- Lawrence Llewelyn-Bowen - 42
- Vinnie Jones - 61
- Tom Jones - 72

National Eisteddfod of Wales: Chair - Twm Morys
National Eisteddfod of Wales: Crown - Mererid Hopwood
National Eisteddfod of Wales: Prose Medal - Cefin Roberts
National Eisteddfod of Wales: Music Medal - Owain Llwyd
Wales Book of the Year:
- English language: Sugar and Slate - Charlotte Williams
- Welsh language: O! Tyn y Gorchudd - Hunangofiant Rebecca Jones - Angharad Price
Gwobr Goffa Daniel Owen - Elfyn Pritchard, Pan ddaw'r dydd
John Tripp Award for Spoken Poetry: Emily Hinshelwood

October - The Welsh rugby union team participate in the Rugby World Cup in Australia. Having defeated Canada 41-10, Tonga 27-20, and Italy 41-10, they lose to New Zealand 37-53 and to England 17-28 to go out of the competition.