diff --git a/Signal/src/ViewControllers/ContactViewController.swift b/Signal/src/ViewControllers/ContactViewController.swift
index d7df9e117..9914c33e5 100644
--- a/Signal/src/ViewControllers/ContactViewController.swift
+++ b/Signal/src/ViewControllers/ContactViewController.swift
@@ -736,7 +736,9 @@ class ContactViewController: OWSViewController, CNContactViewControllerDelegate
             owsFail("\(ContactViewController.logTag) could not open address.")
             return
         }
-        guard let url = NSURL(string: "http://maps.apple.com/?address=\(escapedMapAddress)") else {
+        // Note that we use "q" (i.e. query) rather than "address" since we can't assume
+        // this is a well-formed address.
+        guard let url = NSURL(string: "http://maps.apple.com/?q=\(escapedMapAddress)") else {
             owsFail("\(ContactViewController.logTag) could not open address.")
             return
         }