diff --git a/completions/bash/brew b/completions/bash/brew
index 3889b95b04782..714db8a36a326 100644
--- a/completions/bash/brew
+++ b/completions/bash/brew
@@ -2576,6 +2576,7 @@ _brew_upgrade() {
       --mdimporterdir
       --no-binaries
       --no-quarantine
+      --overwrite
       --prefpanedir
       --qlplugindir
       --quarantine
diff --git a/completions/fish/brew.fish b/completions/fish/brew.fish
index 2d38de8b1d35f..72db0e25353da 100644
--- a/completions/fish/brew.fish
+++ b/completions/fish/brew.fish
@@ -1680,6 +1680,7 @@ __fish_brew_complete_arg 'upgrade' -l language -d 'Comma-separated list of langu
 __fish_brew_complete_arg 'upgrade' -l mdimporterdir -d 'Target location for Spotlight Plugins (default: `~/Library/Spotlight`)'
 __fish_brew_complete_arg 'upgrade' -l no-binaries -d 'Disable/enable linking of helper executables (default: enabled)'
 __fish_brew_complete_arg 'upgrade' -l no-quarantine -d 'Disable/enable quarantining of downloads (default: enabled)'
+__fish_brew_complete_arg 'upgrade' -l overwrite -d 'Delete files that already exist in the prefix while linking'
 __fish_brew_complete_arg 'upgrade' -l prefpanedir -d 'Target location for Preference Panes (default: `~/Library/PreferencePanes`)'
 __fish_brew_complete_arg 'upgrade' -l qlplugindir -d 'Target location for Quick Look Plugins (default: `~/Library/QuickLook`)'
 __fish_brew_complete_arg 'upgrade' -l quarantine -d 'Disable/enable quarantining of downloads (default: enabled)'
diff --git a/completions/zsh/_brew b/completions/zsh/_brew
index 3f006c5a78794..bac18a885499d 100644
--- a/completions/zsh/_brew
+++ b/completions/zsh/_brew
@@ -2071,6 +2071,7 @@ _brew_upgrade() {
     '(--formula)--mdimporterdir[Target location for Spotlight Plugins (default: `~/Library/Spotlight`)]' \
     '--no-binaries[Disable/enable linking of helper executables (default: enabled)]' \
     '--no-quarantine[Disable/enable quarantining of downloads (default: enabled)]' \
+    '(--cask)--overwrite[Delete files that already exist in the prefix while linking]' \
     '(--formula)--prefpanedir[Target location for Preference Panes (default: `~/Library/PreferencePanes`)]' \
     '(--formula)--qlplugindir[Target location for Quick Look Plugins (default: `~/Library/QuickLook`)]' \
     '(--formula)--quarantine[Disable/enable quarantining of downloads (default: enabled)]' \
@@ -2086,7 +2087,7 @@ _brew_upgrade() {
     '(--casks --skip-cask-deps --greedy --greedy-latest --greedy-auto-updates --binaries --require-sha --quarantine --appdir --keyboard-layoutdir --colorpickerdir --prefpanedir --qlplugindir --mdimporterdir --dictionarydir --fontdir --servicedir --input-methoddir --internet-plugindir --audio-unit-plugindir --vst-plugindir --vst3-plugindir --screen-saverdir --language)--formula[Treat all named arguments as formulae. If no named arguments are specified, upgrade only outdated formulae]' \
     '*::installed_formula:__brew_installed_formulae' \
     - installed_cask \
-    '(--formulae --build-from-source --interactive --force-bottle --fetch-HEAD --ignore-pinned --keep-tmp --debug-symbols --display-times)--cask[Treat all named arguments as casks. If no named arguments are specified, upgrade only outdated casks]' \
+    '(--formulae --build-from-source --interactive --force-bottle --fetch-HEAD --ignore-pinned --keep-tmp --debug-symbols --display-times --overwrite)--cask[Treat all named arguments as casks. If no named arguments are specified, upgrade only outdated casks]' \
     '*::installed_cask:__brew_installed_casks'
 }
 
diff --git a/docs/Manpage.md b/docs/Manpage.md
index 78a9ecc880ac9..e859bfdb28978 100644
--- a/docs/Manpage.md
+++ b/docs/Manpage.md
@@ -806,6 +806,8 @@ upgraded formulae or, every 30 days, for all formulae.
   Generate debug symbols on build. Source will be retained in a cache directory.
 * `--display-times`:
   Print install times for each package at the end of the run.
+* `--overwrite`:
+  Delete files that already exist in the prefix while linking.
 * `--cask`:
   Treat all named arguments as casks. If no named arguments are specified, upgrade only outdated casks.
 * `--skip-cask-deps`:
diff --git a/manpages/brew.1 b/manpages/brew.1
index 8a6e43e168b85..8c95e9766c6b8 100644
--- a/manpages/brew.1
+++ b/manpages/brew.1
@@ -1118,6 +1118,10 @@ Generate debug symbols on build\. Source will be retained in a cache directory\.
 Print install times for each package at the end of the run\.
 .
 .TP
+\fB\-\-overwrite\fR
+Delete files that already exist in the prefix while linking\.
+.
+.TP
 \fB\-\-cask\fR
 Treat all named arguments as casks\. If no named arguments are specified, upgrade only outdated casks\.
 .