Fistula thrombosis should be treated as soon as possible or within 48 hours. The duration and site of arteriovenous fistula thrombosis as well as the type of access are important determinants of treatment outcome. Timely declotting allows immediate use without the need for a central venous catheter. Thrombi become progressively fixed to the vein wall, which makes surgical removal more difficult. Thrombosis may affect the post-anastomotic vein segment as result of anastomotic stenosis or may begin at the needle site. When the clot is localized at the anastomosis in radial-cephalic and brachial-cephalic fistula, the outflow vein may remain patent due to the natural side branches that continue to carry venous blood flow. In these accessess it is possible to create a new proximal anastomosis. Thrombosis in transposed basilic vein fistula usually leads to clot propagation of the entire vein. Although comparative studies are missing, the available literature suggests that thrombosed autogenous arteriovenous fistula should, preferably, be treated by interventional radiology. The single exception may be forearm arteriovenous fistula, thrombosed due to anastomotic stenosis. It is likely that in such cases, proximal re-anastomosis will provide good results.