First, it is not advisable to self-drive to Milford Sound with or without chains in winter. There is a high risk of ice, which chains will not help and an additional risk of the road closing due to avalanche or fresh snow. Safer to take a bus.
Whether you need chains will depend on exactly where you are going. Again it is safer not to travel if there roads are covered in snow. In June this is quite unlikely unless a sudden storm comes through.
If you have some flexibility in your schedule, and if you are not going places where chains will definitely be required eg ski fields, you can get away with not having chains. For example, if you will be based in Queenstown, and it snows heavily, you can just wait until it clears or get the shuttle. As suggested, you are better off taking a coach tour to Milford Sound in winter.
But if you have a tight itinerary and will be driving over high passes, you should have chains. But maybe this is not the right itinerary for you?
I decided to cancel my rental car reservation and am planning to book a tour. Better safe than sorry! Thank you for your help.
I am quite flexible to my itinerary and will be based on Queenstown and will not go skiing. just wanted to drive around Milford sound, Te Anau, Glenrocky and Cromwell, but after reading reply, I made mind to cancel my rental car reservation to go to Milford sound. Then, here' s another question, is it alright to drive from Glenocky, Queenstown to Cromwell without snow chains and only during daytime(10am to 4~5pm)?
In answer to your question about driving from Queenstown to Glenorchy without chains - yes, absolutely. Most of the year this is absolutely fine. Be cautious of ice, but as long as you leave late enough in the morning that the sun has got onto the road you will be fine. If there is a big storm, the roads might be tricky and chains might be wise, but in that case you would be better off just postponing your trip for another day.
This advice also applies to other trips you might want to make out of Queenstown eg Arrowtown, Cromwell etc.
The Milford road is a special case because of the risk of road closure due to avalanche - as you will see when you get there!
Thakns million! My problem solved!