All 3 and 4 year olds in England are entitled to 570 hours’ free childcare per year. These hours are usually taken over 38 weeks (during term-time) and so equate to 15 hours per week. Your child’s nursery may ask you to complete paperwork to ensure that your child gets the funding he or she is entitled to but you do not need to apply for a code with the County Council for this.
All University of Oxford and community nurseries operate the 15 hours scheme, though how funds are allocated may vary, e.g. some nurseries may ‘stretch’ the free hours over a full calendar year. Funding is applied to your fees the term after your child's third birthday.