I work with a number of clients that are at or near retirement, so this question comes up a lot. Everyone wants to know when they should get out of stock funds and move completely to bonds for income. The simple answer is never. Here are a few points to consider:
First, just because you are retired does not mean that you will no longer being living a full and active life. Many of my clients will live, statistically, 20 years in retirement. To me, that is a long time. Stocks have proven to outperform bonds over the long term and you need growth of a portfolio to keep ahead of inflation.
Secondly, there are a number of stock funds that pay nice dividends. A combination of dividend paying stock funds + bond mutual funds may provide the income you need in retirement while your portfolio continues to grow.
Lastly, I had a conversation last week with a 92 yr. old client who does not wish to change from his moderately aggressive risk tolerance. He likes the growth he has realized, and still has a lot of things he would like to do.

There is no set time at which your portfolio mix has to change. Your lifestyle and health will determine your mix.

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