47 motor insurance claims were made in Mayo last year, relating to uninsured or untraced drivers.
The number of claims from Co Mayo was up 7% since 2016 last year and by 52% since 2015.
The Motor Insurers’ Bureau of Ireland received over 2,700 such claims last year.
The non-profit organisation was set up to compensate victims of accidents caused by uninsured vehicles.
The MIBI says that, since 2016, it has witnessed a significant step up in the number of claims they received.
It's also concerned about fraudulent claims - with 1 in 8 thought to be suspicious.