diff --git a/src/blockchain_utilities/blockchain_utilities.h b/src/blockchain_utilities/blockchain_utilities.h
index 78487b995..e8615cf86 100644
--- a/src/blockchain_utilities/blockchain_utilities.h
+++ b/src/blockchain_utilities/blockchain_utilities.h
@@ -33,7 +33,7 @@
 
 // bounds checking is done before writing to buffer, but buffer size
 // should be a sensible maximum
-#define BUFFER_SIZE 1000000
+#define BUFFER_SIZE (2 * 1024 * 1024)
 #define CHUNK_SIZE_WARNING_THRESHOLD 500000
 #define NUM_BLOCKS_PER_CHUNK 1
 #define BLOCKCHAIN_RAW "blockchain.raw"