Paul Davies, Assembly Member for Preseli Pembrokeshire, is urging local charities to become more accountable to donors and the public.
Last year over 1,000 of the 9,000 charities in Wales were late in sending their accounts to the Charity Commission, the independent regulator of charities in Wales and England.
To combat this, the Commission's Wales Office has launched a campaign to improve accountability by contacting Welsh charities that have not sent in their information.
All registered charities must send financial information every year to the Commission.
This information can then be accessed on the online Register of Charities by anyone who wants to find out more about a charity. The register entry of any charity that is late in sending the Commission its financial information is marked with a red banner.
Paul Davies, AM for Preseli Pembrokeshire, said:
"There are over 300 charities in Preseli Pembrokeshire, carrying out a huge range of activities, from delivering meals-on-wheels to teaching children about local wildlife. Many of these charities rely on the generosity of local people to continue with their work.
It's really important that people feel involved with and informed about the ways in which charities spend donations and the best way of finding out about this is to look at the Register of Charities on the Charity Commission website."
Harry Iles, Head of the Charity Commission Wales Office, said:
"We have a fantastic tradition in Wales of helping charities and many people do this by donating money. It is essential that charities demonstrate to donors they are transparent, accountable and well run; they can do this by ensuring that their entry on the Register of Charities is up-to-date.
"Getting accounts in on time has become even more important for charities as funds become harder to find. We are calling on all trustees to look at their register entry on our website and check that they have sent all their documents in on time. A red banner may be the deciding factor for someone who wants to support the charity, so we want all Welsh charities to stay out of the red."
The new Charity Commission initiative aims to improve the timely submission of accounts and annual returns by Welsh charities. The Commission will also be working with the Wales Council for Voluntary
Action and charity funding organisations in Wales to publicise the campaign. The Commission's overall goal is to ensure charities are effective, accountable and well-run so that they can continue to make a vital contribution to every aspect of life in Wales.