Harry, who saw action on the front line during two tours of duty in Afghanistan, will be in civilian dress for official events including the late monarch’s state funeral.
Only working royals – which Harry and Andrew are not – are being permitted to dress in uniform at five ceremonial occasions.
These are the St Giles’ Cathedral service in Edinburgh, which took place on Monday, and the coffin’s procession to Westminster Hall, the vigil at the lying in state, the funeral in Westminster Abbey and the committal service in Windsor.
But an exception has been made for Andrew who will wear a uniform as a “special mark of respect” for the Queen when he stands guard around her coffin during the Vigil of the Princes.
He is expected to be joined by the Queen’s other children – the King, the Princess Royal and the Earl of Wessex – at the proceedings during the lying in state later this week.
It is likely to be a bitter blow for ex-solder Harry, who is proud of his decade in the forces, and who was saddened after being stripped of his honorary military roles including Captain General of the Royal Marines by the Queen post-Megxit.
Earlier on Monday, he wrote of his special memories of when the Queen attended his passing out parade in 2006 when he became an officer in the British Army.
He told of his “first meeting” with his Granny as “my Commander-in-Chief” – and was believed to be referring to the occasion when the late monarch made him grin and blush while she reviewed the cadets.
A source confirmed Harry – whose rank is a captain – would not be in uniform for any events.
Andrew stepped down from public life after the furore over his friendship with paedophile billionaire Jeffrey Epstein.
He went on to pay millions to settle a civil sexual assault case to a woman he claimed never to have met.
In January, ahead of his legal settlement, the Queen stripped him of all of his honorary military roles, including Colonel of the Grenadier Guards, and he gave up his HRH style.
Andrew, a former Royal Navy officer who served in the Falklands War, retained his rank as a Vice Admiral, and is expected to wear the coinciding uniform.
Virginia Giuffre sued him for allegedly sexually assaulting her when she was 17 after she was trafficked by Epstein. Andrew denied the claims.
At the service of thanksgiving in St Giles’ on Monday, Andrew was in a morning suit, while his siblings, including Edward who dropped out of the Royal Marines, wore military dress as they processed behind the Queen’s coffin.
Andrew wore eight medals and decorations – his South Atlantic Medal for service in the Falklands, his Silver, Golden, Diamond and Platinum medals, a Royal Navy Long Service Medals with Bars, Canadian Forces Decoration with Bar and New Zealand Commemoration Medal.
At the Duke of Edinburgh’s funeral in April 2021, the dress issue was dealt with by the Queen who decided that no members of the royal family should wear uniform.
It was a break with tradition but seen as the most eloquent solution to the problem.
Reports had suggested Andrew was considering wearing the uniform of an admiral.
He was due to be promoted to Admiral in 2020 to mark his 60th birthday, but this did not go ahead following the fallout from his disastrous Newsnight appearance.