diff --git a/Library/Homebrew/os/mac/version.rb b/Library/Homebrew/os/mac/version.rb
index 9fbf14398e..c8849dc436 100644
--- a/Library/Homebrew/os/mac/version.rb
+++ b/Library/Homebrew/os/mac/version.rb
@@ -27,13 +27,13 @@ module OS
       # TODO: bump version when new macOS is released or announced
       # and also update references in docs/Installation.md and
       # https://github.com/Homebrew/install/blob/HEAD/install.sh
-      MACOS_NEWEST_UNSUPPORTED = "12.0"
+      MACOS_NEWEST_UNSUPPORTED = "13"
       private_constant :MACOS_NEWEST_UNSUPPORTED
 
       # TODO: bump version when new macOS is released and also update
       # references in docs/Installation.md and
       # https://github.com/Homebrew/install/blob/HEAD/install.sh
-      MACOS_OLDEST_SUPPORTED = "10.14"
+      MACOS_OLDEST_SUPPORTED = "10.15"
       private_constant :MACOS_OLDEST_SUPPORTED
 
       sig { params(version: Symbol).returns(T.attached_class) }
diff --git a/docs/Installation.md b/docs/Installation.md
index ee86685e7b..bb2712269a 100644
--- a/docs/Installation.md
+++ b/docs/Installation.md
@@ -12,7 +12,7 @@ it does it too. You have to confirm everything it will do before it starts.
 ## macOS Requirements
 
 * A 64-bit Intel CPU or Apple Silicon CPU <sup>[1](#1)</sup>
-* macOS Mojave (10.14) (or higher) <sup>[2](#2)</sup>
+* macOS Catalina (10.15) (or higher) <sup>[2](#2)</sup>
 * Command Line Tools (CLT) for Xcode: `xcode-select --install`,
   [developer.apple.com/downloads](https://developer.apple.com/downloads) or
   [Xcode](https://itunes.apple.com/us/app/xcode/id497799835) <sup>[3](#3)</sup>
@@ -78,7 +78,7 @@ Uninstallation is documented in the [FAQ](FAQ.md).
 <a name="1"><sup>1</sup></a> For 32-bit or PPC support see
 [Tigerbrew](https://github.com/mistydemeo/tigerbrew).
 
-<a name="2"><sup>2</sup></a> 10.14 or higher is recommended. 10.9–10.13 are
+<a name="2"><sup>2</sup></a> 10.15 or higher is recommended. 10.10–10.14 are
 supported on a best-effort basis. For 10.4-10.6 see
 [Tigerbrew](https://github.com/mistydemeo/tigerbrew).