Does splitting your files into .cpp and .h decrease compile time?

I have a big .cpp file with several classes defined and declared in one single file. I was thinking of having a .h file for each class but I am not sure about the advantages.

Is splitting your files pure preference? Would this increase compile time AND/OR general readibility? My compiler gives me a list of all class declarations that I can easily access with one click, hence if the compiler needs more time putting all those files together, I rather keep it in one chunk.

Edit: I am asking splitting into .cpp and .h and not multiple cpp's as this question has been dismissed that there is already an answer.

Having multiple files will not directly decrease the time, however as compilation can be carried out differentially, where only changed code is re-compiled to object files before linking means that if you have each set of classes in their own .cpp and .h files you can potentially save a lot of time. It also has corollary effects such as:

• debugging is more straight-forward: you have a smaller file to work through to locate and correct any bugs and errors.
• code will be clearer and more maintainable generally
• if utilising makefiles you can selectively compile files to achieve a time saving
• easier to re-use code: you can take any given part of your code over to a new project without inheriting all the parts you do not want/need
• easier to document each class independently
• easier to control revisions/more suited to source control
• easier and more efficient to deploy code updates, rather than sending a whole new mega-file with 20 classes you can send just the ones which have changed.

This is by no means an exhaustive list, just a brief introduction really, and there can be almost as many arguments against it as for, but in general the pros outweigh the cons for me.