Is using a Revocable Trust the only way I can avoid probate in South Dakota?

No. Actually, there are several other ways to avoid probate. For example, if you own assets in a "joint tenancy" with one or more others, those assets will pass by law to the survivor(s) when you die, and will not pass under probate.

However, you should be careful before creating a joint account, because the joint tenant will have rights in the joint property as soon as you create the account. Payable-on-Death (POD) bank accounts and other assets that are payable to designated beneficiaries such as proceeds from life insurance policies or pension benefits will also avoid probate. Transfer-on-death (TOD) designations for real estate, securities and motor vehicles also avoid probate.