diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8dafe03..eae4ce1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -478,10 +478,32 @@ if(APPLE)
   )
 endif()
 if(USE_LIBIDN2 AND NOT WIN32)
-  # The prebuild makes libidn2 self-contained with its included libunistring.
+  # The prebuild makes libidn2 self-contained with its included libunistring,
+  # except for iconv: libunistring's striconveh.c calls the plain POSIX
+  # iconv()/iconv_open()/iconv_close() symbols, which are not part of
+  # a static archive's own link requirements, so they must be supplied again
+  # here when libidn2.a gets linked into curl. On Apple platforms iconv is
+  # not part of libSystem's implicit re-exports (unlike on glibc) and always
+  # needs to be linked explicitly; pinning the absolute path to Apple's
+  # /usr/lib/libiconv.dylib (rather than a bare -liconv) guarantees this
+  # resolves to the system copy even when a package manager's own libiconv
+  # is reachable on the linker search path.
+  #
+  # LIBIDN2_LIBRARY must carry both paths as one CMake list value (curl's
+  # FindLibidn2.cmake forwards it verbatim into an INTERFACE_LINK_LIBRARIES
+  # property). This ExternalProject_Add(curl ...) call's CONFIGURE_COMMAND
+  # is a plain command list, so a literal ";" here would already be split
+  # into separate command-line words by CMake's own configure-time list
+  # handling before it ever reaches the nested cmake invocation - use the
+  # same LIST_SEPARATOR token ("|", declared below) already used for
+  # CMAKE_IGNORE_PREFIX_PATH/CMAKE_IGNORE_PATH above for the same reason.
+  set(_libidn2_link_libs "${DEPS_INSTALL_DIR}/lib/libidn2.a")
+  if(APPLE)
+    string(APPEND _libidn2_link_libs "|@ICONV_PREFIX@/lib/libiconv.dylib")
+  endif()
   list(APPEND _curl_staged_dependency_args
     "-DLIBIDN2_INCLUDE_DIR=${DEPS_INSTALL_DIR}/include"
-    "-DLIBIDN2_LIBRARY=${DEPS_INSTALL_DIR}/lib/libidn2.a"
+    "-DLIBIDN2_LIBRARY=${_libidn2_link_libs}"
   )
 endif()