The Abortion Bill has passed all stages of the Oireachtas.
27 senators voted in favour of the Health (Regulation of Termination of Pregnancy) Bill 2018 and five against.
The Bill will now be presented to the President for signature.
Speaking as the Bill completed its passage in the Seanad, Health Minister Simon Harris said: "This is a genuinely historic moment. It paves the way for the implementation of the service for termination of pregnancy in January 2019.”
The legislation permits terminations to be carried out up to 12 weeks of pregnancy; or where there is a risk to the life, or of serious harm to the health, of the pregnant woman; or where there is a risk to the life, or of serious harm to the health, of the pregnant woman in an emergency; or where there is a condition present which is likely to lead to the death of the foetus either before or within 28 days of birth.
The Minister said: "I would like to acknowledge my colleagues in the Oireachtas for their co-operation, their thoughtful contributions and for the long hours everyone has put in to see it through.
"I want to thank the campaigners who fought for 35 years to change a nation, to change hearts and minds. I want to thank the minority who fought the battle in here when it was convenient for the majority to ignore.
Deirdre Duffy, the Campaign Manager for Together for Yes, said: "This is a truly momentous day for women in Ireland. Today, the final hurdle for Together for Yes has been crossed. For the first time ever since the establishment of the state, women who become pregnant in Ireland are now safe and protected by compassionate legislation. The harm and suffering the Eighth has caused for women is now only a memory and as a nation we will ensure that women are never treated this way again in Ireland.
"2018 will be recognised as a turning point in how this country respects and treats women. This year has unleashed a new women's movement across the generations who are now determined to overcome all remaining challenges to achieve real and lasting gender equality.
Colm O'Gorman, Executive Director of Amnesty International Ireland, said: “We welcome the passage of this bill, and fully appreciate the importance of its enactment by year’s end so that abortion services can begin in January.
“Women have waited 35 years for this, the daily violations of their human rights must come to an end. However, we and the government want to avoid a situation where the law prevents pregnant people from accessing the healthcare they need, or delaying their care. We don’t want women continuing to travel or accessing illegal abortion pills online. That is not what people voted for on 25 May.
“We know from exit polls following the vote in May that 62% of people voted yes because they agreed with a women’s right to choose and 55% voted because they viewed access to abortion as a women’s health issue. The new abortion legislation will ensure that most women will be able to access services in Ireland and this is a major step forward.
“But as the law is currently drafted, we have some serious concerns that barriers to women accessing timely care remain. And there are some significant flaws. These include the potentially high and ambiguous threshold created by the language on ‘serious harm’ to a women’s health, the lack of provision of access in cases of pregnancies with severe rather than fatal foetal impairments, the mandatory waiting periods, and the continued criminalisation of health professionals.”