Operating spacecraft at End -Of -Life (EOL) presents a lot of challenges. For spacecrafts with multi -tank propulsion system, one of the problems i s propellant migration between tanks due to temperature difference between tanks, so called thermal pumping. Propellant migration can deplete one of the tanks even though the total propellant load of the spacecraft does not indicate any possibility of tank depletion. The thermal pumping should be taken into consideration at EOL when amount of propellant migrating in and out of the tank is comparable with propellant load of a single tank. The paper discusses an Active Propellant Management (APM) approach t o control propellant migration in order to reduce risk of an accidental depletion of a single tank in multi -tank propulsion system. A reduction of the propellant migration is accomplished by using tank heaters to control propellant movement between tanks. The paper discusses possible APM implementations, like temperature difference driven vs. time line driven. It shows that the most common approach, namely, temperature difference driven APM may lead to a more dangerous propellant distribution than it tri es to mitigate. The paper also discusses effect of propellant migration on re -pressurization procedures for satellites with blow -down multi -tanks propulsion system.