switzerland hut to hut hiking in late may

Right at the very top of the page on the right hand side is the coat of arms of the Swiss Alpine Club. From there go straight across to the left side of the page where it starts off de | fr | it |en Click the "en" and the page will turn into English.

Late May is early for hut-to-hut hiking in the Swiss alps. Also, many of the SAC huts are not on through-routes, but instead are situated for climbing peaks, so they are at the "end of the road" so to speak. There are some that are along through-routes, as well as private mountain inns that serve hikers. But linking these may involve crossing high passes that will be snow-covered and possibly dangerous in May. Or they may be sitting atop the high pass, such as Blumlisalphütte on the Höhtürli:
http://www.bluemlisalphuette.com/ This one, perched on a peak above Grindelwald, does not open until late June: http://www.berghotel-faulhorn.ch/ In other words, you are going to have trouble finding a hut route that is open that early. consider village-to-village hiking at lower elevations instead. You might find doable routes among the Swiss national or regional trails. This website is one guide: http://wanderland.myswitzerland.com/en/routen_list.cfm?tour=route&art=national If you don't find anything appealing among the 7 national trails, go back one page and try the regional trails-shorter, but there are 60 to choose from.

It is too dangerous to hike on higher ground around mountains in late May. It is still "flash food" season due to snow melt.