The Duchess of Sussex will become Patron for The National Theatre,The Association of Commonwealth Universities,Smart Works and Mayhew.
Queen Elizabeth II has passed on patronages for The National Theatre and The Association of Commonwealth Universities, roles the Queen has held for 45 and 33 years respectively, to Duchess Meghan, 37, and the pregnant royal will also take on Patronage of two additional charities as part of her official working portfolio - Smart Works and Mayhew.
Meghan - who is married to Prince Harry - will be supporting the National Theatre as she is a "strong believer in the arts" and believes they can be used to join different communities.
The official Kensington Palace Twitter account wrote: "The duchess is a strong believer in using the arts to bring people from different backgrounds and communities together. @NationalTheatre's mission is to make world class theatre that's entertaining, challenging and inspiring - and to make it for everyone."
The former 'Suits' actress will also take over the Association of Commonwealth Universities, the world's first and oldest international university network, and the only organisation representing higher education across all 53 Commonwealth countries, as she believes in "accessible education for all".
The duchess - who was known as Meghan Markle prior to her marrying into the British Royal Family - will also be working with Mayhew, a charity which uses innovative ways to reduce the number of animals in need through proactive community, and educational initiatives and preventative veterinary care.
Kensington Palace tweeted: "The duchess has long understood the connection between animals and community welfare."
Finally, Meghan will work alongside Smart Works, a company which helps long term unemployed and vulnerable women regain the skills, confidence and tools to succeed at job interviews, return to employment and transform their lives.