Does rooting erase sim contacts?

I don't think so, and I never really checked, but besides, all of your contacts should be synced with your google account, so it won't really matter because when you are given the opportunity to sign back into your google account after the root, your contacts are back on your phone, and I'm sure you could save them back to your sim card if needed.

 

no

 

No, but as you may or may not know ... SIM cards have very limited storage space for contacts ... and are not the best place to have your contacts for backup purposes...

Suggest you also regularly even back up your online contacts to a csv file ... so that even if you move to a non-android/google phone ... you will have the file for importing into a different make/style of phone.