Deferred sentences (where the DUI charge is completely dismissed upon successful completion of the court probation period) are no longer authorized for a DUI sentence.
Only suspended sentences (where DUI conviction remains on the criminal record after probation successfully completed) are now allowed for a DUI sentence.
However deferred sentences are still authorized for reduced DUI charges, i.e. for Reckless Driving, Negligent Driving 1° and Reckless Endangerment. But they still will count as a “prior DUI conviction” at a future DUI sentencing under RCW 46.61.5055.