Hi,

Obviously it depends which resort you are in and and what you eat, but skiathos compares well with other greek islands (we thought it would be more pricy!). I would say we spent around £25-30 for a meal for 2 adults/2 kids including starters, mains and drinks. We often bought 2/3 starters and 2 mains to share as that was plenty for us.

HTH

As Li-sa says, it can depend on which resort you are in but as a rough guide (for 2 adults) We were paying anywhere between 30 to 40 euros for 2 courses with a kilo of wine and a couple of other drinks besides.
However, there are places where you can eat a lot cheaper if you look around.
For instance,when i was out there in September, one restaurant in Koukanaries had a 3 course meal on offer for 10 euros per person!
Some of the grill houses in the streets of the old town in skiathos are excellent value too!