In Russia, Kazakhstan and Belarus
Russia
Under Art. 70–71 of the Labour Code it is no more than 3 months, and up to 6 months for managers and chief accountants. Probation is not set for pregnant women, employees under 18 and some others. An employee who “has not passed” can be dismissed with 3 days’ notice stating the reason; the employee can also leave with 3 days’ notice.
Kazakhstan
In Kazakhstan the probation period is also set in the employment contract, as a rule no more than 3 months (longer for managers).
Belarus
In Belarus probation at hiring is no more than 3 months, not counting time of illness and other periods of absence.
Sources: Labour Code of the Russian Federation («Трудовой кодекс РФ»), ConsultantPlus