People caring for older, seriously ill or disabled loved ones in Wales are missing out on £66 million in allowances.
Carers Wales say a lack of advice and education has left thousands of carers without vital financial support.
The Department of Work and Pensions says the system is being simplified to increase the take-up of benefits.
Alexandra Lodge reports
More top news
There is likely to be a good deal of cloud around today, thickest in the southeast, where outbreaks of rain are possible at times.
A dry night with clear spells for most, especially towards the north where it will become rather chilly with some mist patches possible.
Wales head coach Warren Gatland says some players suffered a few bumps and bruises during their clash against Ireland.