In this post, we've mostly talked about a set start/stop sinking fund. These are just like they sound; they start on a certain date and stop on a certain date. The other type of sinking fund is a revolving sinking fund. This is where the account is never "full," and it's never "empty." I personally mostly use these types of sinking fund accounts. For example, I have a car repair fund. When I set it up, I totaled up the yearly car cost (i.e., oil changes, added $300 for new tires (I get them every other year or so), and then about $1300 for any repairs that need to be done. Then I added it all up, and let's estimate that it was $2000 total. So $2,000 / 12 months = $166.67 a month goes into our car repair fund. Every month money goes in, and some months money goes out to pay for a car expense.