The Islands Visitor Survey 2012-2013 found more than 425,000 people visited Orkney, Shetland and the Outer Isles, with about three quarters saying they would be very likely or fairly likely to return in the next five years for a holiday or short break.
Visitors contributed more than £100million to the economies of the areas surveyed, which come under Scotland's three islands council but do not include the Argyll islands.
Conducted between October 2012 and last September, the poll asked almost 4000 people a range of questions as they left the areas , including the reason for their visit, where they stayed and what they visited during their trip.
One noticeable change from previous surveys is that about 40% of visitors now share their experiences online during and after their trip, with almost a third uploading photos of their visit on social media sites. Visitor satisfaction levels to these islands were very high, with about 80% of visitors stating they were "very satisfied" with their visit.
Increases were recorded for all, but it is not easy to say how big they were. Shetland, for example attracted 64,655 overnight/day visitors with a total spend of £16m during the time of this survey. Approximately 60,000 visited in 2006, according to an earlier poll.
Orkney attracted 142,816 visitors, spending more than £31m over 2012/2013. This compares to the 141,974 recorded in a survey in 2008/2009.
The Outer Isles attracted 218,196 people, spending more than £53.5m in 2012/2013, against 171,136 in 2006.
Mike Cantlay, chairman of VisitScotland, said: "Tourism is a key economic driver for many of Scotland's islands, as the Islands Visitor Survey has clearly demonstrated."