Its free for the first year it is out, you got time.
If you really feel that you are not going to take it I can easily tell you how to remove it.
***Doing so may cause you not to be able to take the free upgrade and may well cause the earth to fall out of its planetary orbit and plunge directly into the sun... its your dollars.
First open Windows Update and click “Installed Updates” in the bottom-left corner.
Find KB3035583, you can sort by name. Once you’ve located it, right-click and choose “Uninstall”.
When you select to uninstall this update, you’ll be asked to confirm and then you will need to restart your computer
it will be gone, until you download and install the next round of windows updates...then it could very well come back.