The deeply conservative kingdom is one of the most gender-segregated countries in the world, where women live under the supervision of a male guardian, cannot drive, and must wear head-to-toe black garments in public.
But Saudi media outlets have reported that the country`s King Salman bin Abdulaziz Al Saud has issued an order allowing women to benefit from government services such as education and healthcare without getting the consent of a male guardian.
Last month there was outrage when the country was elected to the UN`s women`s commission, whose role is to shape "global standards on gender equality and the empowerment of women".
The UK Foreign Office refused to deny Britain had voted for Saudi Arabia`s ascension to the body, but Belgium`s prime minister said he "regretted" his ambassador`s vote in favour.
The new changes mean women could, in some circumstances, study and access hospital treatment, work in the public and private sector and represent themselves in court without consent of a male guardian, said Maha Akeel, a women`s rights campaigner and a director at Jeddah-based Organisation of Islamic Cooperation.
"Now at least it opens the door for discussion on the guardian system," Ms Akeel told the Thomson Reuters Foundation. "Women are independent and can take care of themselves."
It comes as the latest in a series of moves in Saudi Arabia to include women more in the workforce as the kingdom moves to diversify its economy and cut reliance on oil.
The trend started in 2011 when the late King Abdullah allowed women onto the government advisory Shura Council. Women can now vote in municipal elections, work in some retail and hospitality jobs and were allowed to compete in the Olympics for the first time in 2012.
However Saudi Arabia was still ranked 141 of 144 countries in the 2016 Global Gender Gap, a World Economic Forum study on how women fare in economic and political participation, health and education.
The system of ma;e guardianship, which requires women to obtain permission from a guardian - father, husband, or son - to travel, study or marry is an impediment to realising women`s rights, say rights groups.
"Male guardianship is un-Islamic and humiliating for women," said Ms Akeel. "Some (men) take advantage of this male guardianship for their own benefit and abuse it."