I put "excel shortest path" into my favorite internet search engine and got several hits. This was the first one: http://www.excel-easy.com/examples/s...h-problem.html I would suggest you start by studying this and other examples of the shortest path problems. Then work on adapting those examples to your specific scenario here. If you have trouble with a specific part of the algorithm, let us know and we'll see what we can do to help.