diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -921,9 +921,11 @@
                     {RPCResult::Type::NUM, "nTx",
                      "The number of transactions in the block"},
                     {RPCResult::Type::STR_HEX, "previousblockhash",
-                     "The hash of the previous block"},
+                     /* optional */ true,
+                     "The hash of the previous block (if available)"},
                     {RPCResult::Type::STR_HEX, "nextblockhash",
-                     "The hash of the next block"},
+                     /* optional */ true,
+                     "The hash of the next block (if available)"},
                 }},
             RPCResult{"for verbose=false", RPCResult::Type::STR_HEX, "",
                       "A string that is serialized, hex-encoded data for block "
@@ -1056,9 +1058,11 @@
                     {RPCResult::Type::NUM, "nTx",
                      "The number of transactions in the block"},
                     {RPCResult::Type::STR_HEX, "previousblockhash",
-                     "The hash of the previous block"},
+                     /* optional */ true,
+                     "The hash of the previous block (if available)"},
                     {RPCResult::Type::STR_HEX, "nextblockhash",
-                     "The hash of the next block"},
+                     /* optional */ true,
+                     "The hash of the next block (if available)"},
                 }},
             RPCResult{"for verbosity = 2",
                       RPCResult::Type::OBJ,
diff --git a/test/functional/rpc_blockchain.py b/test/functional/rpc_blockchain.py
--- a/test/functional/rpc_blockchain.py
+++ b/test/functional/rpc_blockchain.py
@@ -337,6 +337,11 @@
         header.calc_sha256()
         assert_equal(header.hash, besthash)
 
+        assert 'previousblockhash' not in node.getblockheader(
+            node.getblockhash(0))
+        assert 'nextblockhash' not in node.getblockheader(
+            node.getbestblockhash())
+
     def _test_getdifficulty(self):
         difficulty = self.nodes[0].getdifficulty()
         # 1 hash in 2 should be valid, so difficulty should be 1/2**31
@@ -441,6 +446,9 @@
             blockinfo['nextblockhash'],
             blockheaderinfo['nextblockhash'])
 
+        assert 'previousblockhash' not in node.getblock(node.getblockhash(0))
+        assert 'nextblockhash' not in node.getblock(node.getbestblockhash())
+
 
 if __name__ == '__main__':
     BlockchainTest().main()