The 2021 Holland Ladies Tour, also known as the 2021 Simac Ladies Tour is a road cycling stage race that took place in the Netherlands between 24 and 29 August 2021. It was the 23rd edition of the Holland Ladies Tour, and part of the 2021 UCI Women's World Tour.

The Holland Ladies Tour is a women's elite professional road bicycle racing stage race held annually in September since 1998 in the Netherlands. It's a tour with 6 or 7 stages. For sponsorship reasons the 2011 race was officially titled the Profile Ladies Tour, the 2012 race the BrainWash Ladies Tour, from 2013 to 2019 as the Boels Rental Ladies Tour, and in 2021 as the Simac Ladies Tour. The race was not held in 2020.