diff --git a/src/test/addrman_tests.cpp b/src/test/addrman_tests.cpp
--- a/src/test/addrman_tests.cpp
+++ b/src/test/addrman_tests.cpp
@@ -108,7 +108,10 @@
     BOOST_CHECK_EQUAL(addrman.size(), 1);
 
     // Test: New table has one addr and we add a diff addr we should
-    //  have two addrs.
+    //  have at least one addr.
+    // Note that addrman's size cannot be tested reliably after insertion, as
+    // hash collisions may occur. But we can always be sure of at least one
+    // success.
     CService addr2 = ResolveService("250.1.1.2", 8333);
     BOOST_CHECK(addrman.Add(CAddress(addr2, NODE_NONE), source));
     BOOST_CHECK(addrman.size() == 2);