diff --git a/src/chainstate/burn/operations/leader_block_commit.rs b/src/chainstate/burn/operations/leader_block_commit.rs
index a275f8b5f..752fc3f36 100644
--- a/src/chainstate/burn/operations/leader_block_commit.rs
+++ b/src/chainstate/burn/operations/leader_block_commit.rs
@@ -265,6 +265,9 @@ impl StacksMessageCodec for LeaderBlockCommitOp {
         if self.memo.len() > 0 {
             write_next(fd, &self.memo[0])?;
         }
+        else {
+            write_next(fd, &0u8)?;
+        }
         Ok(())
     }