Prince William and Kate Middleton’s heaviest workload awaits when they reach the throne.

The Duke and Duchess of Cambridge are the future king and queen. They won’t be taking over the throne after Queen Elizabeth II as Prince Charles is the heir apparent.

It may still take years when Prince William becomes the monarch. However, by then, the couple would have to face tons of works regardless of their age.

"William and Catherine as King and Queen, assuming they are in good health and an active age when they reach the throne, can expect the heaviest workload of any royals,” royal expert Eliot Wilson said.

This isn’t surprising as Queen Elizabeth II remains one of the hardest-working royals even at her age. The king or queen generally has the most to do of all the members of the royal family.

In the past, being a ruler came with a shorter lifespan due to poor health and risky nature of the job, itself. The modern royal family have calmed down especially the monarch because there is no retirement plan for the one in the highest position.

“The monarch herself (or himself) has shouldered the largest number of engagements and duties for years, and only considerably advancing age has forced Her Majesty to cut back (something I imagine she found very hard, as she has an exceptionally deeply ingrained sense of duty and service),” he explained.

Regardless of Prince William and Middleton’s age, whether they are in their 60s or older when they become king and queen, they should expect much work because they will be the central focus of the royal family in terms of image and workload. He also warned them of the heavy paper works that come with the position.

“Although the position of the monarch is ceremonial, there is a vast amount of paperwork involved; the Queen may not have the power to influence many large-scale political decisions, but she must be informed of them, and she still receives a letter from a Government whip every sitting day which briefs her on the goings-on in Parliament that day,” he added.

At present, the Queen is in Balmoral for her three-month summer vacation. However, according to royal expert Roya Nikkhah, even during her break, she still does her red boxes every single day. She added that being in Balmoral for summer is a “work holiday” for the monarch.

Prince William and Kate Middleton
Prince William and Kate Middleton journey by carriage procession to Buckingham Palace following their marriage at Westminster Abbey on April 29, 2011 in London. Getty Images/Sean Gallup