diff --git a/CHANGES.md b/CHANGES.md
index ad69eae2e5..57abdac4a1 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -8,6 +8,8 @@ profile. This started with version 0.26.0.
 
 ### Changed
 
+- Added back the flag `--disable-outside-detected-project` (#2439, @gpetiot)
+  It was removed in version 0.22.
 - \* Consistent formatting of comments (#2371, @Julow)
 - Documentation comments are now formatted by default (#2390, @Julow)
   Use the option `parse-docstrings = false` to disable.
diff --git a/doc/manpage_ocamlformat.mld b/doc/manpage_ocamlformat.mld
index 2977fddff3..f0f4cdc0db 100644
--- a/doc/manpage_ocamlformat.mld
+++ b/doc/manpage_ocamlformat.mld
@@ -470,11 +470,6 @@ OPTIONS (REMOVED)
        --align-variants-decl=VAL
            This option has been removed in version 0.22.
 
-       --disable-outside-detected-project=VAL
-           This option has been removed in version 0.22. OCamlFormat is
-           disabled outside of a detected project by default, to enable the
-           opposite behavior use `enable-outside-detected-project`.
-
        --doc-comments-val=VAL
            This option has been removed in version 0.16. If you are using
            `doc-comments-val=before` in combination with
@@ -535,6 +530,12 @@ OPTIONS
        --disable-conf-files
            Disable .ocamlformat configuration files.
 
+       --disable-outside-detected-project
+           If no .ocamlformat config files have been detected, disable the
+           formatting. OCamlFormat is disabled outside of a detected project
+           by default, to enable the opposite behavior use
+           --enable-outside-detected-project.
+
        --doc
            Parse input as an odoc documentation.
 
diff --git a/lib/Conf.ml b/lib/Conf.ml
index 5199751279..e08101e39c 100644
--- a/lib/Conf.ml
+++ b/lib/Conf.ml
@@ -277,14 +277,6 @@ module V = struct
   let v0_22 = Version.make ~major:0 ~minor:22 ~patch:None
 end
 
-let disable_outside_detected_project =
-  let msg =
-    "OCamlFormat is disabled outside of a detected project by default, to \
-     enable the opposite behavior use `enable-outside-detected-project`."
-  in
-  let names = ["disable-outside-detected-project"] in
-  Decl.removed_option ~names ~since:V.v0_22 ~msg
-
 let profile =
   let doc =
     "Select a preset profile which sets $(i,all) options, overriding lower \
@@ -349,7 +341,7 @@ let profile =
       {conf with profile= elt; fmt_opts= p} )
     (fun conf -> conf.profile)
 
-let options = Store.[elt disable_outside_detected_project; elt profile]
+let options = Store.[elt profile]
 
 (** Options affecting formatting *)
 module Formatting = struct
diff --git a/lib/bin_conf/Bin_conf.ml b/lib/bin_conf/Bin_conf.ml
index 05280bf891..26b15c6f7c 100644
--- a/lib/bin_conf/Bin_conf.ml
+++ b/lib/bin_conf/Bin_conf.ml
@@ -116,23 +116,35 @@ let enable_outside_detected_project =
       (List.map File_system.project_root_witness ~f:(fun name ->
            Format.sprintf "$(b,%s)" name ) )
   in
-  let doc =
-    Format.sprintf
-      "Read $(b,.ocamlformat) config files outside the current project when \
-       no project root has been detected for the input file. The project \
-       root of an input file is taken to be the nearest ancestor directory \
-       that contains a %s file. If $(b,.ocamlformat) config files are \
-       located in the same directory or parents they are applied, if no \
-       $(b,.ocamlformat) file is found then the global configuration \
-       defined in $(b,\\$XDG_CONFIG_HOME/.ocamlformat) (or in \
-       $(b,\\$HOME/.config/.ocamlformat) if $(b,\\$XDG_CONFIG_HOME) is \
-       undefined) is applied."
-      witness
+  let enable =
+    let doc_enable =
+      Format.sprintf
+        "Read $(b,.ocamlformat) config files outside the current project \
+         when no project root has been detected for the input file. The \
+         project root of an input file is taken to be the nearest ancestor \
+         directory that contains a %s file. If $(b,.ocamlformat) config \
+         files are located in the same directory or parents they are \
+         applied, if no $(b,.ocamlformat) file is found then the global \
+         configuration defined in $(b,\\$XDG_CONFIG_HOME/.ocamlformat) (or \
+         in $(b,\\$HOME/.config/.ocamlformat) if $(b,\\$XDG_CONFIG_HOME) is \
+         undefined) is applied."
+        witness
+    in
+    Arg.info ["enable-outside-detected-project"] ~doc:doc_enable ~docs
+  in
+  let disable =
+    let doc_disable =
+      "If no $(b,.ocamlformat) config files have been detected, disable the \
+       formatting. OCamlFormat is disabled outside of a detected project by \
+       default, to enable the opposite behavior use \
+       $(b,--enable-outside-detected-project)."
+    in
+    Arg.info ["disable-outside-detected-project"] ~doc:doc_disable ~docs
   in
   Term.(
     const (fun enable_outside_detected_project conf ->
         {conf with enable_outside_detected_project} )
-    $ Arg.(value & flag & info ["enable-outside-detected-project"] ~doc ~docs) )
+    $ Arg.(value & vflag false [(true, enable); (false, disable)]) )
 
 let inplace =
   let doc = "Format in-place, overwriting input file(s)." in
diff --git a/test/projects/disable_outside_detected_project.expected b/test/projects/disable_outside_detected_project.expected
new file mode 100644
index 0000000000..84259279e7
--- /dev/null
+++ b/test/projects/disable_outside_detected_project.expected
@@ -0,0 +1,7 @@
+File "main.ml", line 1:
+Warning: Ocamlformat disabled because [--enable-outside-detected-project] is not set and no [.ocamlformat] was found within the project (root: ../disable_outside_detected_project)
+(* The following code should not be formatted *)
+type t = {
+  foooooo : string;
+  baaaaar : Baaaaar.t;
+}
diff --git a/test/projects/disable_outside_detected_project/dune-project b/test/projects/disable_outside_detected_project/dune-project
new file mode 100644
index 0000000000..0636ab6acf
--- /dev/null
+++ b/test/projects/disable_outside_detected_project/dune-project
@@ -0,0 +1 @@
+(lang dune 1.11)
diff --git a/test/projects/disable_outside_detected_project/main.ml b/test/projects/disable_outside_detected_project/main.ml
new file mode 100644
index 0000000000..8f4b7ca2f4
--- /dev/null
+++ b/test/projects/disable_outside_detected_project/main.ml
@@ -0,0 +1,5 @@
+(* The following code should not be formatted *)
+type t = {
+  foooooo : string;
+  baaaaar : Baaaaar.t;
+}
diff --git a/test/projects/dune b/test/projects/dune
index 986f52b6c2..04b905377a 100644
--- a/test/projects/dune
+++ b/test/projects/dune
@@ -41,6 +41,28 @@
  (action
   (diff outside_detected_project.expected outside_detected_project.output)))
 
+(rule
+ (deps
+  disable_outside_detected_project/dune-project
+  disable_outside_detected_project/main.ml)
+ (package ocamlformat)
+ (enabled_if
+  (<> %{os_type} Win32))
+ (action
+  (with-outputs-to
+   disable_outside_detected_project.output
+   (chdir
+    disable_outside_detected_project
+    (run ocamlformat --disable-outside-detected-project main.ml)))))
+
+(rule
+ (alias runtest)
+ (package ocamlformat)
+ (enabled_if
+  (<> %{os_type} Win32))
+ (action
+  (diff disable_outside_detected_project.expected disable_outside_detected_project.output)))
+
 (rule
  (deps
   (source_tree outside_detected_project_with_name))