The planning commission was scrapped on 13 Aug 2014. This was replaced by Niti Aayog.
The new National Institution for Transforming India (NITI) will act more like a think tank or a forum, in contrast with the Commission which imposed five-year plans and allocated resources to meet set economic targets.
Reason NITI Aayog Replaced Planning Commission
The major difference in approach to planning between NITI Aayog and Planning Commission is that the Niti Aayog will invite greater involvement of the states
On the other hand Planning Commission took a top-down approach with a one-size-fits-all plan.
The Planning Commission’s role was the formulation of broad policy and its capacity was more advisory. But NITI Aayog shall have powers for resource allocation to states, based on their respective needs.
The states had little direct say in policy planning, which was the purview of the Planning Commission. Involvement of the states was indirect through the National Development Council which is not the case in the NITI Aayog.
The Planning commission is merely a think tank and does not have any powers. Also, there is no involvement of state and union territories. To resolve these issues Niti Aayog was formed and Planning Commission was scraped.