The phrase estimate at completion, which can also be referred to by the three letter anagram EAC, is an input output device that is used to measure the expected total cost of a particular schedule activity, a work breakdown structure, or of the project as a whole, in cases where the scope of work that has been previously defined will ultimately be completed. The estimate at completion is equal to the amount of actual cost (also know by the anagram of AC) plus the estimate to complete (also known by the anagram of ETC) for the entirety of the remainder of the work. The estimate at completion can be determined by deriving calculations based on the performance to date, or may be derived by the project leader or team via using other miscellaneous factors entirely. The estimate at completion, when updated based on progress to date, is then referred to as a latest revised estimate. See also the terms estimate to complete as well as earned value technique for more information.
This term is defined in the 3rd and the 4th edition of the PMBOK.