The adhesion of blood clots to blood vessels, such as through the adhesion of fibrin, is essential in hemostasis. While numerous strategies for initiating clot formation and preventing dot lysis are being developed to create improved hemostatic agents, strategies for enhancing dot adhesion have not been widely explored. Here, we show that adhesion of blood clots can be increased by adding a previously characterized synthetic polymer that is crosslinked by coagulation factor XIIIa during dotting. Addition of the polymer to normal plasma increased the adhesive strength of clots by 2-fold. It also recovered the adhesive strength of nonadhesive fibrinogen-deficient whole blood dots from <0.06 kPa to 1.9 +/- 0.14 kPa, which is similar to the adhesive strength of a fibrinogen-rich dot (1.8 +/- 0.64 kPa). The polymer also enabled plasma dots to remain adhered under fibrinolytic conditions. By demonstrating that the adhesive strength of dots can be increased with a synthetic material, this provides a potential strategy for creating advanced hemostatic materials, such as treatments for fibrinogen deficiency in trauma-induced coagulopathy.