What is a fair rent increase in Ireland and how often can my landlord raise the rent?

For most private tenancies, a fair and lawful increase is generally no more than the lower of 2% or the applicable annual HICP inflation rate, and rent can normally be reviewed only once every 12 months. Your landlord must give the required written notice and explain how the new rent was calculated. Different rules or exemptions may apply, so check the current guidance and rent calculator on the Residential Tenancies Board (RTB) website. If you believe the increase is unlawful, you can seek advice or refer the issue to the RTB, which decides disputes based on the tenancy’s facts.