Do you need a 4x4 in Iceland?

it depends on mainly 2 things

• what you want to see
• when you want to go 

We had a 4WD and I am happy we did no stress anywhere on the road (except f-roads that were still closed)

Road to Landmannalaugar 13 June

we went there in June so if you mainly go on the ring road and not planning to go out of it, then there is no need for a 4x4. If you want to do any special trips it might be that without a 4x4 you won't be able to go. For example our road to Latrabjarg if it rains you can't pass by a 2WD or at least this is what the owner of our hostel told us. 

Road to Landmannalaugar 13 June

shortcut from Vik

Road to Dettifoss

Svortuloft Lighthouse, saefellsnes peninsula

Latrabjarg

so, it is basically up to you, you can enjoy Iceland for sure with a 2WD but if you want to go off-road...might be safer for you to get a 4WD.