Gst on interstate supply for buyer.

-GST is compulsory for interstate supply of goods.In this case seller registers for gst and charges gst.

-GST registration is compulsory for reverse charge.

my question:- Is GST registration compulsory for buyer if he deals( i.e.buys) in interstate supply of goods and is not covered under reverse charge.Buyers turnover does not exceed 20 lacs only is he buys from other state.

Thanks