Commercial Licence for Mac and Windows?

Hi,

Accordingly to http://www.jetbrains.com/phpstorm/buy/buy.jsp#commercial :

Commercial licenses that are registered in a legal entity name allow for use of the software on any computer, operating system, and by any developer within a legal entity, provided that the total number of concurrent users never exceeds the number of purchased licenses.

If PhpStorm will be used exclusively by you, then you may go for Personal License:

Who qualifies

If you plan to purchase yourself a license, and you are the only person planning to use that license, then the Personal License is for you. Personal licenses are non-transferable.

Personal License allows you to use it on Windows and Mac ( http://www.jetbrains.com/phpstorm/buy/buy.jsp#personal ):

Cross-platform compatibility

A Personal License allows for use of the software on different operating systems, provided that they are not used at the same time.

License Comparison: http://www.jetbrains.com/phpstorm/buy/license-matrix.jsp