Nicola Stugeron has announced a ban on household visits across Scotland to help bring coronavirus “back under control”.
The new regulations are set to come into effect on Friday, although it is being urged people comply from Wednesday.
Speaking at the Scottish parliament, Sturgeon announced further measures to tackle rising Covid-19 cases including all bars and restaurants having to close at 10pm from Friday, in line with changes announced for England.
She said she is keeping having a so-called circuit breaker, or short period of nationwide lockdown, under review.
The first minister urged people in Scotland not to book travel overseas for the October break “unless it is absolutely essential” and advised people against car sharing with those outside of their own household.
She said while the majority of new coronavirus cases in recent weeks are in those under the age of 40, a rise is now being seen in the older population.
The first minister said: “It kills too many old and vulnerable people.
“And for younger, healthier people, while the risks of dying from it are much lower – though not non-existent – it can still result in long-term, serious health problems.
“That’s why action to bring it back under control is necessary – and to bring the R number down again, the action we take now must go beyond the step we announced almost two weeks ago to restrict indoor and outdoor gatherings to six people from two households.”
The move is one step further than England, which has opted to shut bars and restaurants from 10pm and shrink the size of visitors at weddings from 30 to 15.
Sturgeon defended the measures saying that figures indicate the ban on household visits already introduced in the west of Scotland has reduced the spread of the virus and Test and Protect information shows a “high proportion of new cases come from social interactions between different households in our homes”.
Sturgeon added: “Therefore, difficult though it is, any serious effort to reduce the R number below one must take account of this key driver of transmission and seek to break it.
“So after careful consideration, we have decided that from tomorrow, to be reviewed after three weeks and with exceptions that I will come on to, visiting other households will not be permitted.”
Those living alone will be able to form extended households, while couples not living together, those who need childcare and tradespeople will be exempt from the measures.
Addressing reports that measures in Scotland could be in place for up to six months, the first minister said she hopes that will not be the case.
She told MSPs: “It is certainly the case, until scientific developments such as a vaccine change the game in the battle against Covid-19, it will have an impact on our lives.
“That doesn’t necessarily mean that all of the new restrictions I am announcing today will be in place for six months.
“By acting early and substantially, our hope is that these new measures will be in place for a shorter period than would be the case if we waited longer to act.”
The new measures put in place for Scotland will be reviewed every three weeks, she added.