diff --git a/build/osx/wxcocoa.xcconfig b/build/osx/wxcocoa.xcconfig
index c238589daf..0aabf84400 100644
--- a/build/osx/wxcocoa.xcconfig
+++ b/build/osx/wxcocoa.xcconfig
@@ -4,9 +4,17 @@ WXTOOLKITUPPER = COCOA
 #include "wx.xcconfig"
 
 MACOSX_DEPLOYMENT_TARGET = 10.10
+MACOSX_DEPLOYMENT_TARGET[arch=arm64] = 11.0
 
 GCC_VERSION =
 
-ARCHS = i386 x86_64
+// Set ARCHS explicitly for when Xcode stops targeting x86_64 by default.
+// Unknown targets are ignored by Xcode (arm64 requires Xcode 12 or later).
+ARCHS = x86_64 arm64
+
+// Using i386 as a target results in a deprecation error since Xcode 10 (first
+// a warning in 9). If Xcode 9 or earlier is used and the i386 target is also
+// needed, one solution is to enable the following line locally.
+//ARCHS = i386 x86_64
 
 OTHER_LDFLAGS = -framework WebKit -framework IOKit -framework Carbon -framework Cocoa -framework AudioToolbox -framework OpenGL -framework AVFoundation -framework CoreMedia -framework Security -framework QuartzCore -weak_framework AVKit
diff --git a/docs/changes.txt b/docs/changes.txt
index c089de2cd1..c6bba1ebd9 100644
--- a/docs/changes.txt
+++ b/docs/changes.txt
@@ -182,6 +182,10 @@ Changes in behaviour which may result in build errors
 - Under macOS, 10.11 SDK is the minimum SDK, building and deploying under 10.10.5 and
   higher is supported, you must use at least Xcode 7.2.1.
 
+- wxOSX Xcode projects no longer include the i386 target by default and,
+  with Xcode 12 or later, build for the arm64 architecture in addition to
+  existing x86_64. See build/osx/wxcocoa.xcconfig for more information.
+
 - wxPGProperty ctors are not longer public since this class is intended to be
   a base class and should not be instantiated directly.