Safety intravenous catheters (IVCs) are disclosed herein having a catheter hub with a catheter tube, a needle with a needle hub, and a needle guard. The needle guard is configured to be positioned at least partially within an interior space of the catheter hub and is retained thereto by mechanical engagement between the two. Following removal of the needle from the catheter hub, the needle guard is configured to disengage from the catheter hub and attach over a tip of the needle to shield the needle tip from inadvertent needlesticks. The needle guard having an angled end section configured with a length and a width to retain the needle tip within a tip holding space behind the angled end section.