Candidates for the post of General Assistant (Wash Up) must be flexible, punctual, reliable and "able to work well in a team", according to a job description on the Royal Household website.
Although the post is based at Buckingham Palace, the job requires travel away from London for up to two months of the year.
A Buckingham Palace spokesman told The Daily Telegraph: "It is a very small, tight team and they retain that small team atmosphere when they move around.
"When the court moves to Balmoral or elsewhere, so does the team."
The starting salary is £14,200 per year.