Forever. If your conviction is after July 1, 2000, your fines, court costs, interest etc. called Legal Financial Obligations or LFO's can be collected for perpetuity. It is outrageous in my opinion and places an undue burden on defendants who have served their time. LFO's grow at 12% annually. Fortunately, it appears the Courts in Washington must now consider your ability to pay and are waiving at least some of the LFO's and interest if indigent. See this blog for more info.