If an individual donates €250 or more in a year, the approved body can claim a refund of tax paid on that donation.
If a company donates €250 or more in a year, the company can claim a tax deduction as if the donation was a trading expense.
In either case nothing for an individual to claim back.
Brendan’s right . It will qualify but only if the Red Cross are aware that you donated €250 and have your contact details , and they then have to send you a form to sign . If the an post donation system is anonymous, it won’t happen