It depends on the extent of the damage. Generally, it costs between $3 and $10 per square foot to repair a block wall. If the mortar is damaged, it will have to be replaced which can cost an additional $2 to $5 per square foot. If the blocks are cracked or missing, they will need to be replaced which can cost an additional $4 to $8 per square foot. And if the drainage system is damaged, that will also need to be repaired which can cost an additional $10 to $15 per square foot.

The cost to repair a block wall can vary depending on the extent of the damage, the location of the wall, and the contractor you choose. However, on average, you can expect to pay around $10-$15 per square foot for repairs. So if your wall is 10 feet wide and 20 feet long, it would cost between $200 and $300 to repair.