The UK uses a fiscal period which spans from 6 April until 5 April annually since it began in medieval England. Authorities implemented this tax system when calendar modifications impacted the Julian and Gregorian calendars producing 6 April as the annual tax period starting date. TheUK Tax Year Uk establishes its own period from 6 April to 5 April because synchronized tax administration requires this schedule for financial reporting purposes. Various organizations fall under tax period obligations in the UK which includes HMRC rules compliance and accurate returns filing for avoidance of HMRC penalties.