AOL is making between 1,200 and 1,400 employees redundant worldwide.
The company said in November it would look to cut its 6,900-strong workforce by a third, but only 1,100 out of the 2,500 people it needed volunteered to go.
"We announced that if we did not reach the target reduction of one-third we would need to follow the voluntary programme with an involuntary action. We had 1,100 employee volunteers for the voluntary programme."
AOL will be "significantly reducing" its staff in the UK but will continue to have a robust advertising operation as well as a consumer offering. Ireland will remain a core technology development centre for the company.
It has announced an "involuntary layoff" in the US and has started the consultation process in 11 European countries.
It has announced plans to shut office in Germany, Finland, Sweden, Norway, Denmark the Netherlands and Spain.
AOL said, "The internet landscape has become increasingly competitive, and we are making difficult choices to take costs out of the business and ensure AOL's sustainability and future success.
"This is never easy particularly when it impacts our employees directly. We are committed to doing everything we can for impacted employees to make sure that their transition from AOL to a new position is as smooth as possible."