A jab that protects against a virus that causes cervical cancer will be given to boys aged 12 to 13 in England.
The policy decision brings England into line with Scotland and Wales.
HPV vaccine is already routinely offered to girls of the same age at secondary school and is free up until they turn 18.
Experts and campaigners have been calling for equal access to the jab, which can also guard against oral, throat and anal cancers.
HPV is the name given to a large group of viruses, which can be caught through any kind of sexual contact with another person who already has it.
Doctors say most HPV infections go away by themselves, but sometimes infections can lead to a variety of serious problems.
For boys, this includes cancer of the anus, penis, mouth and throat.
The vaccine has been offered to girls since 2008 as part of the NHS childhood vaccination programme, with boys being said to benefit through herd protection.
But there is still a risk of infection in those who go on to have sex with other men or with women who have not been vaccinated.
Thousands of boys in England are expected to be vaccinated under the programme each year, which is likely to start from 2019-20.
Girls aged 12 to 13 in Northern Ireland are also eligible for the vaccine, but no decision has been taken on whether to make it available to boys living there.