The couple tied the knot nine years ago at Westminster Abbey on April 29.
They are isolating with their children Prince George, Princess Charlotte, and Prince Louis at their Norfolk home, Anmer Hall.
Kate Middleton and Prince William are celebrating their ninth wedding anniversary in private amid the coronavirus lockdown.
Kate and Prince William share a throwback picture from their wedding on Twitter and thanked fans for their wishes, saying “Nine years ago today – thank you for all your lovely messages on The Duke and Duchess of Cambridge’s wedding anniversary!”