Many times you will see or hear the phrases “letters of administration” or “letters testamentary”. The phrases are so common that many people use them interchangeably. However, the phrases mean different things and should be used carefully.
The phrase “letters of administration” refers to being appointed to serve as personal representative of an estate when either (1) there was no will, or (2) there was a will but there was no named executor or the named executor(s) cannot or will not serve.
The phrase “letters testamentary” refers to being appointed to serve as personal representative as named in the decedent’s will.
A common place where both “letters testamentary” and “letters of administration” are both found is the DE-150 California Judicial Council probate form for Letters. See here: