Not really that simple a question. The height, length and what the wall is retaining will factor in as well as the regional location. But in general, a poured in place concrete retaining wall is about 20% less than a concrete block retaining wall. Natural stone is another matter altogether and will also depend on size and type of stone used.

Depends on the wall. For us here in VA, a drystacked stone wall less than 24 inches tall is less expensive than a poured or block wall on a frost footer. Above that stone becomes prohibitive because of the mass and width needed at the base.

In addition to what GG said, where I live, a permit is required for any retaining wall more than three feet high.

Several years ago we had a retaining wall installed; it is made if concrete blocks that look like stone. Much cheaper than a true stone wall.

Thanks so much beautiful!