The First Minister told MSPs there may be continued restrictions on travel to the islands.
She said travel to other parts of the UK and the common travel area, which includes Ireland and the Channel Islands, will “hopefully” also be permitted from Monday April 26, “or as soon as possible thereafter”.
Ms Sturgeon said tourist accommodation across Scotland will re-open with restrictions from that date.
Driving lessons and tests will be permitted then too.
The First Minister said she was “certain” international travel from Scotland would not be possible before Monday May 17 but “it may well not be possible for a further period after that”.
She added that pre-departure and post-arrival testing was “very likely" for some time.
Ms Sturgeon said: “We expect that from April 26, restrictions on journeys within mainland Scotland will be lifted entirely.
"However, if restrictions on socialising and hospitality are relaxed more quickly and significantly on the islands, there may be a need to retain some restrictions on travel to and from the mainland - to protect island communities from the importation of new cases.
"However, rather than impose that decision now on our island communities, we intend to discuss it directly with them to determine what arrangements they consider will work best for their circumstances.
"We hope that restrictions on journeys between Scotland and other parts of the UK and the wider common travel area can also be lifted, if not on April 26, then as soon as possible thereafter.
"However, we need to keep this under review, as part of our efforts to reduce the risk of new cases being imported into Scotland and we will update the position during April.
“Reducing the risk of importing new cases – and new variants - is also directly relevant to the issue of international travel.
“We intend to discuss with the aviation sector later this week how and when non-essential travel to some international destinations may be possible again.
“Like the UK government, we are certain that this will not be achievable before May 17.
"However, our view is that it may well not be possible for a further period after that.
“And, even when overseas travel does resume, it is very likely that a requirement for pre-departure and post-arrival testing will remain in place for some time to come.”
A spokesman for Edinburgh Airport said: "Although this is a welcome change in direction from the Scottish Government, our experience is one of words, backed with no engagement, and even less action.
“We hope this signals a change in their approach and allows us to move forward together with purpose and optimism.
"The admission that testing will be required for some time to come is not surprising as we knew this would be needed and consistently called on a regime to be adopted, even working closely with Scottish Government clinicians on proposals.
“What is surprising is they then stonewalled Scotland's main airports and refused to share advice submitted to ministers despite the airports funding the clinical reports.
"This is not the constructive engagement the industry is crying out for."