diff --git a/doc/manual/nix-instantiate.xml b/doc/manual/nix-instantiate.xml
index 9488bb7338..a3d67debe6 100644
--- a/doc/manual/nix-instantiate.xml
+++ b/doc/manual/nix-instantiate.xml
@@ -35,7 +35,7 @@
         <arg choice='plain'>
           <option>--eval-only</option>
           <arg><option>--strict</option></arg>
-          <arg><option>--no-readonly-mode</option></arg>
+          <arg><option>--read-write-mode</option></arg>
         </arg>
         <arg choice='plain'><option>--find-file</option></arg>
       </group>
@@ -141,7 +141,7 @@ policies.</para>
 
   </varlistentry>
 
-  <varlistentry><term><option>--no-readonly-mode</option></term>
+  <varlistentry><term><option>--read-write-mode</option></term>
 
     <listitem><para>When used with <option>--eval-only</option>,
     perform evaluation in read/write mode so nix language features
diff --git a/src/nix-instantiate/nix-instantiate.cc b/src/nix-instantiate/nix-instantiate.cc
index 1f4d1ffab8..6a93acf396 100644
--- a/src/nix-instantiate/nix-instantiate.cc
+++ b/src/nix-instantiate/nix-instantiate.cc
@@ -107,7 +107,7 @@ void run(Strings args)
             settings.readOnlyMode = true;
             evalOnly = true;
         }
-        else if (arg == "--no-readonly-mode") {
+        else if (arg == "--read-write-mode") {
             settings.readOnlyMode = false;
         }
         else if (arg == "--parse-only") {