It was founded in March 2013 by the merger of SNR Denton, Fraser Milner Casgrain and Salans.

[9] As of December 2023, Dentons maintains its position as the largest law firm in the world by number of attorneys, a distinction it has held since 2015.

Following the combination, Dentons surpassed Baker & McKenzie and DLA Piper, two of the world's previously largest law firms by headcount, by at least 2,500 lawyers.

[17] In April 2015, Dentons US agreed to a merger with Atlanta-based law firm McKenna Long & Aldridge which was completed in June of that year.

In December 2016, Dentons launched in Australia and Papua New Guinea by combining with leading Australian law firm Gadens.

[26] On June 2, 2021, Denton announced the launch of Dentons Global Advisors,[27] composed of founding member Albright Stonebridge Group along with a team of seasoned advisory industry leaders, including Ed Reilly, who serves as chief executive officer (CEO).

In 2022, Dentons combined with Zaanouni Law Firm & Associates in Tunisia[31] and LuatViet in Vietnam.

[38] Dentons continues to hold its position as the largest law firm in the world, even following the conclusion of its combination with Dacheng.

[39] In October 2024, Dentons announced that it will launch offerings with four firms across Africa: Tamrat Assefa Liban Law Office in Ethiopia, LEGALIX in Senegal, Kouengoua Minou Nkongho (KMN) in Cameroon, and Pathy Liongo & Associates in the Democratic Republic of Congo.