Are online bill pay services eco-friendly? They at least save a stamp. I'll go ahead and assume that the marginal electricity usage involved in paying the bills online is negligible. Paying bills online saves the paper of an envelope and the load on the postal service to deliver that envelope (gas, time, wear & tear on vehicles). Furthermore, funds are transferred electronically...you save a check and all the handling of that check. Nobody has to process the check, stamp it and sort it, so you save ink and mechanical processes by not writing a check.
Just thinking about this, I may have to start paying more of my bills online. The only problem for me is that my checking accounts don't have an online bill pay option...I have to use my E*Trade account for that, and I don't keep enough cash on hand to deal with all my bills through E*Trade.