Any bank knows to purchase an SSL cert to protect your information. in order for you to know if you are secure look at the http connection. HTTP means you are not protected HTTPS means you are secure. Also the Lock show at the lower right bottom of your web broweser tells you if you are secure or not.
From my personal experience and awareness, if I am going to purchase something online the first thing I look is at the URL whether it`s http or https://
If I don`t see the "S" I move on to the next web site that offers me 128 BIT Encryption. Most of the web sites I develop that have to deal with online transactions, I force my client to purchase an SSL Certificate. For 150 a year you can save yourself a headache and perhaps loose customers.