diff --git a/lib/bitcoind.js b/lib/bitcoind.js
index 02f21d8e..a2eb71f1 100644
--- a/lib/bitcoind.js
+++ b/lib/bitcoind.js
@@ -530,6 +530,11 @@ Bitcoin.prototype.getBlockByTxid =
 Bitcoin.prototype.getBlockByTx = function(txid, callback) {
   return bitcoindjs.getBlockByTx(txid, function(err, block) {
     if (err) return callback(err);
+    bitcoin.db.get('block-tx/' + txid, function(err, blocks) {
+      blocks = blocks || [];
+      blocks.push({ hash: block.hash });
+      bitcoin.db.set('block-tx/' + txid, blocks, utils.NOOP);
+    });
     return callback(null, bitcoin.block(block));
   });
 };