"Providing access to free period products is fundamental to equality and dignity, and removes the financial barriers to accessing them," Scottish Social Justice Secretary Shona Robison said.
"This is more important than ever at a time when people are making difficult choices due to the cost of living crisis and we never want anyone to be in a position where they cannot access period products," she added.
The bill, which was passed unanimously in 2020, was introduced by Scottish Parliament lawmaker Monica Lennon, who had campaigned against "period poverty" — when someone who needs sanitary products can't afford them.
"Proud of what we have achieved in Scotland," Lennon tweeted Monday. "We are the first but won't be the last."
The Scottish government said its move was world-leading, with countries including South Korea and New Zealand taking similar approaches.
Last year New Zealand's government said all schools in the country were to offer free period products, as part of a drive to help students from poorer families who were missing school because of period poverty.