It is the first country in the world to implement such a law, with the Scottish government believing its introduction will save lives.
The new legislation sets a 50 pence (approximately 70 cents) minimum price per unit of alcohol. Anyone licensed to serve alcohol in the country -- in shops as well as bars and restaurants -- will need to follow the new pricing laws.
One unit is 8 grams of alcohol, which in terms of drinks is equal to a 25-milliliter shot of 40% alcohol, such as whiskey, or 76 milliliters of wine at 13%. A standard 175 millileter glass of 14% wine in the UK is 2.4 units. In the United States, a standard drink is 14 grams of alcohol, equal to 148 millilters of table wine.
The Scottish government said the previously low prices of alcohol were "unacceptable," as people in Scotland could exceed alcohol limit guidelines of 14 units per week for just £2.50 ($3.50) with certain cheap yet strong alcoholic drinks. The same purchase would now cost at least £7.50 ($10.20).
According to a 2016 Scottish Health Survey, one in four people drinks more than the recommended limit of 14 units per week, classed as hazardous or harmful levels.
Scotland has the highest rate of alcohol-related deaths in the UK. There are 22 deaths every week linked to drinking, according to 2015 data by NHS Scotland. In 2015 through 2016, more than 23,400 people were admitted to hospitals for alcohol-related causes.
According to the government, research suggests the new pricing will save 392 lives within five years.
"Given the clear and proven link between consumption and harm, minimum unit pricing is the most effective and efficient way to tackle the cheap, high-strength alcohol that causes so much damage to so many families," First Minister Nicola Sturgeon said.
The legislation was passed by the Scottish Parliament in 2012 but faced opposition and legal challenges.
"They faced significant political opposition, with much of it organized by the alcohol industry," said Ben Hawkins, assistant professor of global health policy at the London School of Hygiene and Tropical Medicine in the UK. Hawkins believes the policy will benefit public health and commends the Scottish government on getting it passed.
Officials "identified a problem and an effective solution to that problem supported by international evidence," Hawkins said.
Today, Sturgeon tweeted her thanks to "those who have stuck with us through the challenges."
Health Secretary Shona Robison said alcohol misuse costs Scotland £3.6 billion ($4.9 billion US) each year.
"We know we need to act now to change people's attitudes towards alcohol, and I am confident that, with the introduction of minimum unit pricing, we are moving in the right direction," she said.
The minimum pricing will mostly affect cheap white ciders and value spirits that are high in alcohol, according to the Scottish government, with most drinks sold in pubs already being above this new minimum.
In 2016, more than half of alcohol sold in served in Scottish supermarkets was sold as less than 50 pence per unit, NHS Scotland data show.
That same year, 17% more alcohol was sold per adult in Scotland than in England and Wales, at 20.2 units per adult per week compared to 17.3 units, mostly from sales in supermarkets and other stores that sell alcohol.
Dr. Catherine Calderwood, Scotland's chief medical officer, said that "As a nation, we drink 40% more than the low-risk drinking guidelines of 14 units per week for men and women."
"That is where this new legislation comes in, and I am confident that over the first five years of its operation, minimum unit pricing will reduce the number of alcohol-specific deaths by hundreds, and hospital admissions by thousands." she added.