The Aviva Stadium has been confirmed as a designated venue under the Sale of Tickets Act 2021.
It means all rugby and football games at the stadium will be covered by the law, which criminalises the reselling of tickets above their original value at designated events and venues.
The status comes into effect at midnight, but does not apply to tickets already sold.
It comes as the FAI said tickets for the upcoming World Cup qualifier clash between the Republic of Ireland and Portugal at the Aviva Stadium are circulating online at inflated prices.
The stadium is set to host over 51,000 fans for the first time in two years for the sold-out clash on 11 November.
Some early release tickets for next month's rugby test between Ireland and New Zealand at the same venue are also selling online for hundreds of euro more than their face value.
In a statement, an IRFU spokesperson said: "The Aviva Stadium company applied for designation, as a designated venue under the Sale of Tickets Act 2021.
"This application is for all ticketed events at the Aviva Stadium, including football and rugby.
"Designation has been confirmed to us and comes into effect from just after midnight tonight, ahead of our general ticket sale tomorrow at noon.
"The message to all supporters remains clear – do not buy tickets from unofficial ticket sources."
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Opposition parties have said that the legislation, which was enacted last July, was not working.
Speaking on RTÉ's Morning Ireland, Sinn Féin's enterprise spokesperson Louise O'Reilly said it was very obvious that the Ireland-Portugal match was going to sell out.
Ms O'Reilly said that the Government needs to take a good hard look at how it can be proactive and help fans avoid being gouged by ticket touts.
She said she was really disappointed that Tánaiste Leo Varadkar did not designate the match for protection under the legislation.
Ms O'Reilly said the FAI should also have applied for the event to be designated, but if the industry is not going to be proactive then the onus is on the Government to use the powers to protect fans.
"The legislation has essentially fallen at the first hurdle," she said.
Speaking this afternoon, Mr Varadkar said: "This is new legislation. It's only been enacted in the last couple of months so under the legislation the initial onus is on the organiser or the host of the event to designate it.
"What we're going to do over the coming few days is sit down with Croke Park, sit down with the Aviva, sit down with the major sporting bodies ... and suggest to them the advantages of having those events designated.
"The FAI have put that application in now. Perhaps they should have done it sooner, perhaps we should have acted sooner, but this is new legislation and those meetings are going to happen over the next couple of days."
Earlier, a Department of Enterprise said no application for designation of the Ireland-Portugal match was received and that "therefore the event is not designated" under the legislation.
A spokesperson said the legislation applies to venues and events and applications for designation can be made through the department's website free of charge.
Labour's enterprise spokesperson Aodhán Ó Ríordáin said he can appreciate that this may have caught some people by surprise, as restrictions were only lifted last Friday, and there was no "scramble for tickets" for recent games again against Serbia and Khazakstan.
But speaking on RTÉ's Drivetime, he said the Government must now learn from the situation.
"While I understand that Lansdowne Road is now going to be a designated venue, there are quite a number of venues I think we could pre-empt and designate immediately," he said.
"It would mean we wouldn’t have to be firefighting when a big event happens and when these tickets go on sale on websites."