The answer is RIGHT NOW. Pick a retirement age. Lets say 65. Lets say you plan on living until 95. If you start saving at the age of 30 to reach a million by 65 you must save $33,333 per year. This is assuming your investments will keep up with inflation each year. How much money are you saving per year? Devise a plan now. Do not put it off. The future will be here before you know it.