The change to the national HPV vaccination programme backed by the UK's Joint Committee on Vaccination and Immunisation will go ahead from the start of the next academic year.
Research had shown the antibody response to two doses of Gardasil in adolescent girls was as good as a three-dose course, prompting the European Commission to grant marketing authorisation for the reduced schedule.
In a letter to GPs and the wider NHS, officials said that under the new schedule the first dose can be administered at any time during school year eight. The second dose should be administered at least six months and not more than 24 months later.
Public Health England recommended a 12-month gap between doses to reduce the number of vaccine sessions required.
However, a three-dose schedule will be retained for girls who receive their first dose aged 15 or over, as the antibody response is lower in this age group.
The HPV national vaccination programme was introduced in 2008 and is routinely offered to girls aged 12 and 13.