When filing in alphabetical order where do you file Mc? Alphabetizing

After Mb and before Md.

I've done filing for years, and have never separated the "Mc" names from any of the rest of the M's.

Mac or Mc are treated as being the same, the order being taken from the next letter in the name. Mac and Mc are filed before 'simple' M names e.g. MacMillan is filed after McLeod and both are filed before Martin. Hope this helps.