Can someone who is physically or mentally disabled have an SMSF?

Yes, but if they are mentally disabled they will generally be unable to be a trustee of their fund or a director of a corporate trustee. However, superannuation law specifically caters for these people by allowing the person’s guardian or anyone who holds an “enduring power of attorney” to be the trustee of their fund or director of the trustee company, in their place. This is quite common. As people with SMSFs get older, they will nominate someone such as an adult child to be a trustee in their place.