Hello dhamill,
Let me assist you with paying your vendors online.
Do you want to add a check number when paying a vendor online? If so, we can only add a payment amount and process date in the Pay bills online screen (see screenshot below).
Check out this article for more details about paying bills online: Paying bills in Online Bill Pay.
Your satisfaction is our top priority, so if there is anything we can do to improve your experience, please us your feedback. It would help provide a better service in the future and be greatly appreciated.
Click the Gear icon and select Feedback to send one.
Please to let me know if your situation doesn't match what is being discussed above. I'll be around to help you anytime.