Kate will join her husband Prince William to greet President Xi Jinping of China and his wife Peng Liyuan at Buckingham Palace, and is expected to select a tiara from the Queen's personal collection for the historic state visit.
Here, HELLO! profiles some of the stunning royal tiaras that Kate could choose from…
Cartier 'Halo' tiara
The Cartier Halo is the first tiara Kate borrowed from the royal collection for her wedding day in 2011. Named because of its halo shape, it is formed of a band of graduated scrolls featuring 739 brilliant and 149 baton diamonds.
The tiara was originally bought as a love token by the Duke of Cambridge's great-grandfather, the future George VI, for his wife Elizabeth, who later gave it to their daughter Princess Elizabeth as a gift on her 18th birthday.
A closer look at the Cartier Halo tiara.
Cambridge Lover's Knot tiara
William's mother Diana, Princess of Wales received this tiara as a wedding gift from the Queen. Because of its association with Diana – and of course its Cambridge name – this stunning design could also be a contender for Kate.
The tiara was created in 1914 for Queen Mary and features pearls suspended from diamond love knots, however Diana said the tiara was so heavy it induced a headache and she had to switch to her Spencer family tiara instead.
Girls of Great Britain and Ireland Tiara
The Girls of Great Britain and Ireland tiara is said to be one of the Queen's favourite headpieces, so there is onlt the smallest of chances that Kate will be wearing it on Tuesday evening. It is the tiara Her Majesty is often depicted wearing on coins and stamps and originally belonged to Queen Mary, who gave it to her granddaughter Princess Elizabeth as a wedding present in 1947.
A closer look at the Girls of Great Britain and Ireland tiara.
Lotus Flower tiara
Kate wore the dainty Lotus Flower tiara to the Queen's annual diplomatic reception at Buckingham Palace in 2013, and may well choose it again for Tuesday's state banquet. The much-loved piece once belonged to the Queen Mother and started out as a necklace before being transformed into a tiara, crowned by diamond arches and studded with pearls.
Lotus Flower tiara
The Queen mother gave the Lotus Flower tiara to Princess Margaret in the 1950s and it soon became a favoured piece. It was returned to the royal collection after Margaret's death in 2002.
Queen Mary's Fringe tiara
Worn by the Queen on her wedding day, this tiara holds sentimental and historical value within the royal collection. The stunning headpiece was created from 47 diamond bars using stones taken from a necklace Queen Mary had been given by Queen Victoria.
The Fringe tiara was passed on to the future Queen Mother in 1936 and was loaned to her daughter as the "something borrowed" element of her wedding outfit in 1947, before being worn by Princess Anne on her wedding day in 1973.
Queen Mary's Fringe tiara was worn by the Queen on her wedding day.
Another of the Queen's favourite pieces, the Vladimir Tiara once belonged to the Grand Duchess Marie of Russia and was smuggled out during the revolution. The pearl and emerald encrusted design was bought at an auction by Queen Mary and later inherited by Queen Elizabeth on Mary's death in 1953.
The Vladimir tiara could be chosen by Kate for her first-ever state banquet.
The Queen's Sapphire tiara
This striking sapphire and diamond tiara was made at the Queen's request in 1963 using gems from a necklace she had bought. It was designed to match the George VI Victorian Suite jewellery set given to the Queen by her father as a wedding present, and could be the perfect choice for Kate to match her sapphire engagement ring.
Strathmore Rose tiara
The Strathmore Rose tiara once belonged to the Queen Mother and was a gift from her parents for her wedding in 1923. The pretty floral design was inherited by the Queen in 2002 and has not been worn in public for decades, offering Kate the opportunity to revive a treasured piece from the royal collection.
The Royal Family Order of Queen Elizabeth II
Along with a tiara, it is expected that Kate will be accessorising her evening gown with another special piece from the royal collection – the Royal Family Order of Queen Elizabeth II. It is said to be one of the highest honours that can be bestowed on a female member of the royal family, and has already been worn by Princess Anne, the Duchess of Cornwall and the Countess of Wessex.
Kate is the only senior female royal not to have worn the diamond encrusted brooch, which features a plaque of the Queen on a yellow ribbon. Her first state banquet could be the perfect opportunity to do so.