I have a 600d and you can use wireless flash. I haven't really used it much as I'm still learning but you can get flash to fire off camera. Its explained in detail in the camera manual if you have one. You need to go in to the built in flash settings and the second option is for easy wireless flash shooting. The speedlite has to be set as slave and the on camera flash controls it, you have to pop up the on camera flash to make the speed lite fire.
Still a bit new to me so would be grateful if anyone else can explain things a bit better