How do I find out when my patent fees are due?

NO The Patent Office does not notify you. If you go to google and put in USPTO maintenance fees or MPEP maintenance fees it will link you to a full explanation on when you have the window to pay and how to do it as well as the current fees.

As a matter of law, design patents do not require maintenance fees. However, utility patents do require payment maintenance fees during 6 month windows occurring approximately 4, 8 and 12 years after issuance in order to maintain their enforceablity. Maintenance fees can be paid up to 6 months late with the payment of an additional surcharge. If you fail to pay the maintenance fee, the patent will lapse into abandonment and become unenforceable. So, only your utility patent No. 7,934,846 will require the payment of issue fees to maintain its enforceability. Accordingly, your first maintenance fee window opens, March 3, 2014 and should be paid prior to the surcharge date, November 4, 2014. A late payment of your maintenance fee with a surcharge will be accepted up until May 4, 2015. Your patent counsel should remind you of the deadline and cost to pay your maintenance fees and will offer to facilitate those payments. But, if you have a reliable docketing (calendaring) system, you can and should keep track of the maintenance fee deadlines yourself. Additionally, you can make the maintenance fee payments directly without assistance of counsel.

Your attorney should be keeping you informed about when the fees are due. Otherwise, here is a website that can help you http://www.uspto.gov/patents/process/maintain.jsp.

Dear Patent Holder, You can find your maintenance fee information at the USPTO website. Here is a link to display your information. You will need your patent number and the patent application number. Your information will be displayed and you will have an option to pay the fees online.

Design patents have no maintenance fees. Utility patent maintenance fees are due for payment between years 3-4; 7-8 and 11-12 - measured from the date of issuance. The earliest date for payment is thus 3 years from the issue date; then 7, then 11. The last date for payment is on the 4th, 8th and 12th anniversary of issuance - and payments made after 3.5, 7.5, and 12.5 require a "late payment" surcharge fee in addition to the maintenance fee payment. A reminder is sent to the address of record once the surcharge date has been passed and no payment received. Fees and the exact payment schedule are available on the Patent Office website - www.uspto.gov.