Do I need an active AdSense account BEFORE I become a YouTube partner?
You may monetize eligible videos without associating an AdSense account with your YouTube account, if you've enabled monetization for your account.
In order to be paid, you will need to associate an AdSense account, but if you're not ready to do that right away, we'll remind you.
After successfully associating the two accounts, YouTube may deposit a bonus into your AdSense account. The bonus is designed to thank you at a level commensurate with your video monetization contribution before you associated an AdSense account. Once you've successfully linked AdSense and YouTube, your future earnings from the ads served with your videos can be viewed in AdSense and in YouTube Analytics.