The Irish Cancer Society received €1.1 million from the #nomakeupselfie campaign which went viral on social media last month.
The craze saw people post a picture of themselves without makeup online, alongside a charitable donation, before nominating somebody else to do the same.
Communications manager for fundraising Donna Parsons said: "The #nomakeupselfie donations had pretty much stopped by March 27th.
“It was resuscitated briefly after being mentioned on the Saturday Night television programme on March 29th but it finished after that.
Despite being short lived, it helped us raise a huge amount of money out of nowhere.
“We’re about to launch a new five-year breast cancer research programme, which will cost more than €7 million, so this money will help us towards that.”
The Irish Cancer Society would like to see the #nomakeupselfie, or something similar, develop into an annual event.
Ms Parsons said: “In terms of work to be done in research and funding we still have a long way to go, there is no end [to the financial requirements] really.
“The nature of the #nomakeupselfie campaign means it wouldn’t be possible to sustain for a prolonged period, but we would love to see it become annual.
“It probably won’t be selfies again, but anything that can raise this sort of money this quickly again would be brilliant.”
The society’s annual Daffodil Day campaign raises about €4 million.