diff --git a/CMakeLists.txt b/CMakeLists.txt
index 530f54e271..10b4bd89cd 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -680,6 +680,9 @@ endif()
 if(WIN32)
   cmake_dependent_option(CURL_USE_SCHANNEL "Enable Windows native SSL/TLS (Schannel)" OFF CURL_ENABLE_SSL OFF)
   option(CURL_WINDOWS_SSPI "Enable SSPI on Windows" ${CURL_USE_SCHANNEL})
+else()
+  set(CURL_USE_SCHANNEL OFF)
+  set(CURL_WINDOWS_SSPI OFF)
 endif()
 cmake_dependent_option(CURL_USE_MBEDTLS "Enable mbedTLS for SSL/TLS" OFF CURL_ENABLE_SSL OFF)
 cmake_dependent_option(CURL_USE_WOLFSSL "Enable wolfSSL for SSL/TLS" OFF CURL_ENABLE_SSL OFF)