Revenue is experiencing a higher volume of calls due to tenants enquiring about the new rent tax credit.
The measure, introduced in Budget 2023, allows tenants paying rent on private rental accommodation to claim a €500 rent tax credit.
The credit is for 2022 so when a renter claims it, it will result in a refund of €500 going straight into their bank account.
The Government has estimated that some 400,000 people are eligible to claim the credit, and so far the vast majority have not yet done so.
Revenue said demand across all of its PAYE contact channels is traditionally very high throughout the first two months of the year with taxpayers looking to claim credits such as medical expenses.
A spokesperson said, "The new rent tax credit has added to call volumes for this year".
Last week Revenue answered over 16,000 calls from PAYE taxpayers and responded to over 32,000 enquiries from PAYE taxpayers.
Its PAYE telephone service is available Monday to Friday from 9.30am to 1.30pm. However, it said the best method of contacting Revenue is through MyEnquiries, via Revenue's MyAccount portal.
"An enquiry via MyEnquiries enables a taxpayer to have a digital copy of all correspondence with Revenue and the unique correspondence ID generated within can be used to track the progress of the taxpayer's specific query," the spokesperson said.
The Temporary Business Energy Support Scheme (TBESS) helpline reported record call volumes yesterday in line with promotional activity around the scheme and pre-existing claims deadlines.
The Business Taxes Helpline which assists customers registered for IT, CT, CGT, VAT and RCT is also experiencing high volumes of calls currently due to factors such as the CGT payment deadline for disposals made in December 2022 along with the usual refund queries.
Revenue said additional staff are being made available to service increased demand.
"Across all of our customer service channels, Revenue allocates resources to best meet the demand of the various services required," it said.