diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go
index f69d49fd7dd4..f9c3af0de88e 100644
--- a/internal/ethapi/api.go
+++ b/internal/ethapi/api.go
@@ -734,10 +734,10 @@ func (s *BlockChainAPI) GetHeaderByHash(ctx context.Context, hash common.Hash) m
 }
 
 // GetBlockByNumber returns the requested canonical block.
-// * When blockNr is -1 the chain head is returned.
-// * When blockNr is -2 the pending chain head is returned.
-// * When fullTx is true all transactions in the block are returned, otherwise
-//   only the transaction hash is returned.
+//   - When blockNr is -1 the chain head is returned.
+//   - When blockNr is -2 the pending chain head is returned.
+//   - When fullTx is true all transactions in the block are returned, otherwise
+//     only the transaction hash is returned.
 func (s *BlockChainAPI) GetBlockByNumber(ctx context.Context, number rpc.BlockNumber, fullTx bool) (map[string]interface{}, error) {
 	block, err := s.b.BlockByNumber(ctx, number)
 	if block != nil && err == nil {
@@ -2331,6 +2331,15 @@ func (s *BundleAPI) EstimateGasBundle(ctx context.Context, args EstimateGasBundl
 		jsonResult := map[string]interface{}{
 			"gasUsed": result.UsedGas,
 		}
+
+		if result.Err != nil {
+			jsonResult["error"] = result.Err.Error()
+			revert := result.Revert()
+			if len(revert) > 0 {
+				jsonResult["revert"] = string(revert)
+			}
+		}
+
 		results = append(results, jsonResult)
 	}