How long does clonazepam stay in your system?

It is a long acting benzodiazepine and how long it stays in your system partly depends on how you metabolize it. General references give clonazepam a half-life of about 18 to 50 hours. A rule of thumb is that it takes 5 half lives to a drug to be over 97% out of your system. So, with that wide range and not knowing how fast you metabolize it, I would say a minimum of 5 days, more commonly a couple weeks, but could take longer. So, even if you took one 0.5 mg tablet, it would probably be detectable by good screens for at least 4 to 5 days and possibly about 2 weeks. If you take it regularly, do not just stop. Because it leaves your system slowly, you may not develop severe withdrawal symptoms until several days later.