Extract from The FA Handbook 2022-23 Source: The FA

Section 31.18.(C) - Standard Code of Rules for Mini Soccer and Youth Football Competitions

A child who has not attained the age of 6 shall not play, and shall not be permitted or encouraged to play, in a match of any kind.

The relevant age for each Player is determined by his orher age as at midnight on 31 August of the relevant Playing Season i.e. children who are aged 6 as at midnight on 31 August in a Playing Season (together with those who attain the age of 6 during the Playing Season) will be classed as Under 7 Players for that Playing Season. Children who are aged 7 as at midnight on 31 August in a Playing Season will be classed as Under 8 Players for that Playing Season, and so on.

Notwithstanding the above, a child is permitted to play up in the age group above his or her chronological age group, irrespective of any changes of format or competition structure, save that a child who attains the age of 6 after 31 August is permitted to play only in the Under 7 age group, and may not play in the Under 8 age group, for that Playing Season.