From documenting street harassment and sexual assault to calling out sexism on Twitter and beyond, the campaign now operates in 18 countries, has received media coverage around the world and even has its own published book.
"The project has grown bigger than I ever anticipated," Bates told HuffPost UK Lifestyle. "I hoped 100 women might share their stories; now we have 100,000 from people all over the world.
"We set out to raise awareness of gender inequality and we've achieved that with millions of website views and international media coverage from the New York Times to the Times of India."
But what is perhaps even more exciting, she says, is the offline impact the campaign is having on society.
"The entries have been used to work on policy with ministers and members of parliament in multiple countries, to start conversations about consent in schools and universities, to tackle sexual harassment in businesses and workplaces and to help police forces raise the reporting and detection rates on sexual offences," she says.
"On a more individual level, thousands of people have reported the personal impact of the project, from men who have stood up and started challenging street harassers, to women who have reported sexual assault or workplace discrimination for the first time, to girls who have started their own campaigns at school. What started as an awareness-raising activity has become a worldwide movement for equality."
Bates herself is a force to be reckoned with, a leader of the fourth wave feminist movement she is a HuffPost UK blogger, Guardian columnist and regular across broadcast media.
To celebrate the anniversary, Bates has called upon her loyal Twitter following to use the #EverydaySexism hashtag to create a hard-hitting international conversation about the reality of living as a woman today.
We've collated a selection of the tweets below, to highlight the breadth of issues that women are taking a stand against. Tweet yours using the hashtag #EverydaySexism
Of course, the experiences of sexism goes both ways. Routinely men are expected to live up to certain masculine standards and many are starting to fighting back.