May or September?

The tourist population begins to noticeably build in May as the season starts. The summer crowds begin to shrink in early September as visitors return home for the beginning of the school year.

There is not much of an open/closing issue ... both months have less ferry services and sometimes fewer shops etc. But the change I observed (and I've been both times) is nuanced. In Late May-Early June ( May 20-June 15 I confess is now my favorite time), things are open, hotel-owners and boat-owners are out painting. and watering their flowers, they're relaxed, have time to chat, very friendly. In September, hoteliers and taverna-owners have just weathered two months of jampacked European throngs overflowing the place, and people can be a little burned-out. They're thinking about school clothes for their kids, dentist appts in Athens, they're getting ready to move on with their lives. Furthermore, after nearly 4 months with almost no rain, all the greenery on the green islands is ge "brownery", and on the dry islands, even more so. Of course, every home's flowers still bloom with loving care, but the landscape is dusty. And finally... I always feel in late May that I get 1.5 days for every day of holiday, because the sun doesnt' go down until nearly 9 pm. In September it can be dark by 7:30. Just my observations.

I've only made one mid-May to mid-June trip, and a half-dozen in September. Both times are wonderful, but I prefer the fall.

I like the warmer water. I love the figs and pomegranates ripening on the trees, and vegetables in the gardens. If you're lucky, your hotel or pension will allow you to harvest some. I also prefer the quality of light ... somehow it's different in September. I think overall I just like that winding down, end-of-season feeling. People may be tired, but they're also relaxing, because the busy season is almost over.

I was in Greece for three weeks starting at the beginning of October last year in all the places you mention. In some of the places (not Athens) it seemed like we were the last guests to leave the party and hosts were anxious to close up. For example, in a couple places where there were write-ups on this website about the great breakfasts served, we got bare minimum. In one place the room wasn't particularly clean and we heard the comment that they were on reduced staff because end of season closing. So I'd say yes to September but be cautious about carrying over into October.

All the places you mentioned are high-touristed areas even during the off-season such as May and September. Athens never shuts down, Nafplio is a bustling town that stays open year round, Olympia, Delphi & Santorini are very popular year-round also. There "may" be some businesses closing but the majority will be open and running for business so you should not have any problems with a lot being closed. Even still, locals need places to shop, eat and do business.

We've never been to Greece in May, June or Sept. Rather we go every year in October and even the smaller islands have enough open to keep us happy. We've never had any problems with Greeks being ready to shut everything down and rushing us out. In fact we found the locals to be glad the tourist season is over but still need money coming in so are happy to have guests help out with the ecomomy and they are far more relaxed not having to answer to every whim from some pushy and overbearing tourists.

It may also depend on what you want for a Greek Experience: nightlife, shopping, partying or more laid-back, quiet and traditional atmosphere where there are more locals than tourists.

October is lovely, still nice weather, much lower prices and far less tourist. I assume May/early June would be just as nice.

I think either time will give you a better understanding of Greece without a lot of tourists getting in the way!

I have a strong preference for the extra daylight hours of late spring, but in an earlier thread another poster mentioned that for photographers, shorter days are good, because you don't need to get up so early to catch the sunrise. I hadn't thought about that because I take very few pictures.

Thanks everyone! Lots of good things to consider here. Likely leaning slightly toward a mid-May to early June trip, but no final decision for a bit. Thanks.

We were in Naxos and Santorini this past mid May . Loved it, it was more than hot enough for us, and we were swimming in the sea, however , being Canadain we are a tougher lot than many Americans who complian that the pools arent heated in Mexico ( we go to mexico in november and often hear people complai0n about the cold pools , we think they are lovely), and want water temps in the in
80s , we are happy to swim in water that doesnt make us hypothermic in 5 minutes !

However i think both times are great, i had been once before in late sept to october , and it does seem like the locals are a bit tourist burnt out then,,,,but still lovely.