diff --git a/storage/client/client.go b/storage/client/client.go
index 602afca81..90966b99d 100644
--- a/storage/client/client.go
+++ b/storage/client/client.go
@@ -983,7 +983,7 @@ func (c *StorageClient) RuntimeTransactions(ctx context.Context, p apiTypes.GetR
 		ctx,
 		QueryFactoryFromCtx(ctx).RuntimeTransactionsQuery(),
 		p.Block,
-		nil, // tx_hash; filter not supported by this endpoint
+		p.Rel,
 		p.Limit,
 		p.Offset,
 	)
diff --git a/storage/client/queries.go b/storage/client/queries.go
index 89cb96b5c..b2a81ac4f 100644
--- a/storage/client/queries.go
+++ b/storage/client/queries.go
@@ -394,12 +394,25 @@ func (qf QueryFactory) RuntimeBlocksQuery() string {
 
 func (qf QueryFactory) RuntimeTransactionsQuery() string {
 	return fmt.Sprintf(`
-		SELECT round, tx_index, tx_hash, tx_eth_hash, timestamp, raw, result_raw
+		SELECT 
+				%[1]s.runtime_transactions.round,
+				%[1]s.runtime_transactions.tx_index,
+				%[1]s.runtime_transactions.tx_hash,
+				%[1]s.runtime_transactions.tx_eth_hash,
+				%[1]s.runtime_transactions.timestamp,
+				%[1]s.runtime_transactions.raw,
+				%[1]s.runtime_transactions.result_raw
 			FROM %[1]s.runtime_transactions
-			WHERE (runtime = '%[2]s') AND
-						($1::bigint IS NULL OR round = $1::bigint) AND
-						($2::text IS NULL OR tx_hash = $2::text)
-		ORDER BY round DESC, tx_index DESC
+			LEFT JOIN %[1]s.runtime_related_transactions ON %[1]s.runtime_transactions.round = %[1]s.runtime_related_transactions.tx_round 
+				AND %[1]s.runtime_transactions.tx_index = %[1]s.runtime_related_transactions.tx_index
+				AND %[1]s.runtime_transactions.runtime = %[1]s.runtime_related_transactions.runtime
+				-- When related_address ($2) is NULL and hence we do no filtering on it, avoid the join altogether.
+				-- Otherwise, every tx will be returned as many times as there are related addresses for it. 
+				AND $2::text IS NOT NULL
+			WHERE (%[1]s.runtime_transactions.runtime = '%[2]s') AND
+						($1::bigint IS NULL OR %[1]s.runtime_transactions.round = $1::bigint) AND
+						($2::text IS NULL OR %[1]s.runtime_related_transactions.account_address = $2::text)
+		ORDER BY %[1]s.runtime_transactions.round DESC, %[1]s.runtime_transactions.tx_index DESC
 		LIMIT $3::bigint
 		OFFSET $4::bigint`, qf.chainID, qf.runtime)
 }