Buckingham Palace has confirmed that the Duchess of Sussex has given birth to a son.
The announcement of the birth came shortly after 2.30pm today, with both mother and child said to be doing well.
"Her Royal Highness The Duchess of Sussex was safely delivered of a son at 0526hrs.The baby weighs 7lbs 3oz.
"The Duke of Sussex was present for the birth.
"The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, The Duke and Duchess of Cambridge, Lady Jane Fellowes, Lady Sarah McCorquodale and Earl Spencer have been informed and are delighted with the news.
"The Duchess's mother, Doria Ragland, who is overjoyed by the arrival of her first grandchild, is with Their Royal Highnesses at Frogmore Cottage.
"Her Royal Highness and her child are both doing well."
News of the couple's pregnancy was announced to the world in October, just five short months after their wedding at St George's Chapel, Windsor Castle.
In the run-up to the birth, Harry and Meghan confirmed their wishes to keep the arrangements private, amid speculation they had opted for a home birth at their new home Frogmore Cottage, also in Windsor. They also did not find out what they were having, leaving the sex a surprise until today.
Welcome to the world Baby Sussex
The Queen, The Duke of Edinburgh, The Prince of Wales, The Duchess of Cornwall, The Duke and Duchess of Cambridge, Lady Jane Fellowes, Lady Sarah McCorquodale and Earl Spencer have been informed and are "delighted with the news", the palace said.
The statement added that the Duchess's mother Doria Ragland "who is overjoyed by the arrival of her first grandchild" was with the couple at Frogmore Cottage.
The palace said the name of the baby would be announced in due course.
The new arrival will be seventh in line to the throne and the Queen and the Duke of Edinburgh's eighth great-grandchild, and a fourth grandchild for the Prince of Wales.
On announcement of the pregnancy last year, the due date was only revealed to be "in the spring".
Predicted choices for the little boy's name include Arthur, Albert, Frederick, James, Charles and Philip.
Royal births are usually also marked with the traditional custom of placing a framed paper proclamation on an ornate gold stand behind the iron railings of Buckingham Palace.
The baby will not be an HRH or a prince, unless the Queen steps in, because George V limited royal titles in 1917.
A boy will be able to use one of Harry's lesser titles and be known as the Earl of Dumbarton.
The official Instagram account for the Duke and Duchess, @SussexRoyal, also announced the birth saying: "It's a boy! Their Royal Highnesses the Duke and Duchess of Sussex are overjoyed to announce the birth of their child."
What the proud dad had to say following the birth of his son
The Duke of Sussex has been speaking at Windsor following the birth.
A beaming Harry said: "It's been the most amazing experience I could ever have possibly imagined.
"How any woman does what they do is beyond comprehension. But we're both absolutely thrilled.
"We're both absolutely thrilled and so grateful for all the love and support from everybody out there, it's been amazing, so we just wanted to share this with everybody."
He continued to say the couple are still thinking of names for their son and added: "The baby was a little bit overdue so we've had a little bit of time to think about it.
"That's the next bit."
He said he planned to make another announcement in two days' time "so everyone can see the baby".
The Duke added: "I haven't been at many births.
"This is definitely my first birth - it was amazing, absolutely incredible.
"I'm so incredibly proud of my wife.
"And as every father and parent would say, your baby is absolutely amazing.
"But this little thing is absolutely to-die-for so I'm absolutely over the moon."