Meghan Markle has been baptised into the Church of England in a private ceremony conducted by the Archbishop of Canterbury and with Prince Harry at her side, the Daily Mail reported.
Prince Charles and the Duchess of Cornwall were in attendance for the 'intimate', 45-minute service at the Chapel Royal at St James's Palace on Tuesday evening. Neither the Queen nor Prince William were present.
The service reportedly observed the full ritual of the Church with holy water from the River Jordan from the private Royal Family font poured on Markle's head.
Markle, 36, had asked the 62-year-old Archbishop, Justin Welby, to lead the service after forming a close bond with him in recent weeks as he instructed her on the rites and sacraments of the Church, according to reports.
Markle was reportedly confirmed straight after being baptised into the Anglican Church.
She did not need to be baptised in order to marry Prince Harry but reportedly made it clear she wanted to do so out of respect for the Queen's role as the head of the Church of England.
The Daily Mail reported that insiders said it was fitting that the Prince of Wales, who will be the next head of the Church, attended the service.
Markle and Prince Harry will marry on May 19 at St George's Chapel in Windsor Castle. That service will be conducted by the Dean of Windsor, David Connor, with the Archbishop presiding as the couple make their vows.
The Chapel Royal is where Princess Diana's body lay for a week before her funeral in 1997, and where Prince George was christened in 2013. It is also where King Charles I received the Holy Sacrament before his execution in 1649.
For Tuesday's service, the Crown Jeweller Mark Appleby brought the silverware used for Royal Family christenings, including a silver font, basin and flask of holy oil.
Markle had two sponsors to support her – the equivalent of godparents – in accordance with tradition, one of whom was reportedly a close female friend.
The step echoes that of the Duchess of Cambridge, who was baptised as an infant but had a private confirmation after her engagement to Prince William.
According to the Daily Mail, the Chapel Royal choir of six Gentlemen-in-Ordinary and ten Children of the Chapel – claimed to be the oldest continuous musical organisation in the world – performed throughout the service.
Contrary to earlier reports, it was reported that neither Markle's mother, Doria Ragland, or her father, Thomas Markle, who are divorced, travelled from America for the service.
There were reportedly 18 guests who after the ceremony walked to Clarence House, where Charles and Camilla hosted a dinner.
Markle's father was Episcopalian, while her mother belonged to another Protestant denomination.
Markle attended the Catholic Immaculate Heart girls' high school in Los Angeles, despite not being a Catholic herself.
Her first husband whom she married in 2011, Trevor Engelson, was Jewish but she did not convert to his faith. The couple divorced in 2013.
The Church of England conducted 111,500 baptisms in 2017, of which 9 per cent were for those aged over 13.