A record 10,000 women had an abortion at home last year, the British Pregnancy Advisory Service has said.
Pro-choice campaigners welcomed the statistics
It said nearly one-third of the 32,000 terminations it provided in the first nine weeks of pregnancy had been "medical" - involving abortion drugs.
The BPAS described the trend as a "success" for sexual health, but campaign groups have been critical.
Comment on Reproductive Ethics (CORE) accused the BPAS of "deeply insensitive self-promotion" of abortions.
The "abortion pill" is only used in the first nine weeks of pregnancy - later, only surgical termination is allowed.
In a medical abortion, a woman takes the drug mifepristone under supervision, returning two days later to take four pills of misoprostol.
The British Pregnancy Advisory Service then allows them to go home, where the termination takes place within a few hours.
Ann Furedi, chief executive of the BPAS, the UK's biggest independent provider of abortions, said demand for the pills had taken off over the past two to three years - since the service started allowing women to go home after the second dose.
In 2003 BPAS clinics gave 3,500 women early medical abortions (EMAs), but this rose to 5,000 in 2004 and doubled to 10,000 in 2005, the highest ever.
Miss Furedi said: "We're glad that it has been recognised that the best option for women needing abortion is earlier access.
"This trend is a success for BPAS and for the government's sexual health strategy."
A £1m government investment into selected NHS primary care trusts had enabled them to improve early access to abortions, she added, making BPAS the biggest provider of EMA in Europe.
She said women prefer EMAs because they are less invasive, led by nurses, avoid the need for surgery or anaesthesia and bypass sometimes lengthy NHS waiting lists.
But Pressure group Comment on Reproductive Ethics (Core) called BPAS's "trumpeting" its role in the 10,000 abortions "deeply insensitive self-promotion".
"Every rational person, no matter what his or her stance on the rights of the unborn child, has to agree that the ideal for any woman and the health of any nation is fewer, or better still no, abortions," a spokeswoman said.
"BPAS, instead, cannot seem to get enough - the UK figures continue to rise and the government does nothing constructive about it."
Michaela Aston, a spokeswoman for anti-abortion organisation Life, told the Times newspaper mifepristone had been responsible for at least 10 women dying.
But Evan Harris, a Liberal Democrat MP and former hospital doctor, disputed that there had been any deaths and said the abortion pill was far safer than many other drugs.
There was also no evidence the availability of EMA directly leads to an increase in the overall number of abortions, he added.
A Department of Health spokesman said mifepristone's safety was being closely monitored.
"Once a woman has made the difficult decision to have an abortion, and she is legally entitled to one under the grounds of the Abortion Act, then it is better for her to receive one as soon as possible," he said.
"The earlier the abortion is performed the lesser the risk to the woman's health."