However the ECB also said it could reduce qualification to four years, at its own discretion, for players from countries who are not full members of the International Cricket Council.
Cricketers who start living in England and Wales before their 18th birthday need only serve a four-year residency.
Kevin Pietersen, Jonathan Trott, Matt Prior and captain Andrew Strauss, who were all born in South Africa, featured in England's second-test victory over Sri Lanka in Colombo at the start of April.
Pietersen, 31, was involved in the most high-profile switch of international allegiance.
He decided to quit South Africa at the start of his career in protest at a racial-quota system he felt was hindering his prospects.
Soon after completing the qualification process, Pietersen made his test debut in the series victory over Australia in 2005 that helped England regain the Ashes after an 18-year wait.
