diff --git a/src/miner.cpp b/src/miner.cpp
index aed085639..f94ff1d04 100644
--- a/src/miner.cpp
+++ b/src/miner.cpp
@@ -309,7 +309,7 @@ CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn)
             
             // Size limits
             unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
-            if (nBlockSize + nTxSize >= nBlockMaxSize)
+            if (nBlockSize + nTxSize >= nBlockMaxSize-512) // room for extra autotx
             {
                 //fprintf(stderr,"nBlockSize %d + %d nTxSize >= %d nBlockMaxSize\n",(int32_t)nBlockSize,(int32_t)nTxSize,(int32_t)nBlockMaxSize);
                 continue;