Entitlement to Free Home-to-School Transport
The general policy of the County Council is that free transport is provided only for children of compulsory school age (5 years up to 16 years) who:
are under 8 years of age and live two miles or more from the school; or
are 8 years of age and over and live three miles or more from the school.
The ages are taken at 1 September in each school year.
Free transport will be made available to the catchment area school or if applicable, to a suitable school which is nearest to the pupil's home. Free travel may also be offered if the catchment area school is full and a place has been offered by the County Council at another school which is over the distances mentioned above.
Distances are measured using the nearest available route from the gate or access of pupil's home to the gate or access of the school. The type of route measured is one with a hard surface available for all-the-year-round use.
Education and Inspections Act 2006
Under the Education and Inspections Act 2006, free home-to school transport will now be provided to children aged between 8 and 11 years from low income families, who live more than 2 but under 3 miles from their catchment or nearest school.
From September 2008, free home-to-school transport will be provided to children aged 11 to 16, from low income families, who live more than 2 miles but less than 6 miles from their three nearest schools.
Where parents have expressed a preference for a school based on religion or belief, free home-to-school transport may be provided from September 2008 to children aged 11-16, from low income families, who live more than 2 miles but no more than 15 miles from their school.
This is on Suffolk county council website. Don't know if it is the same everywhere