diff --git a/ci/dash/build_src.sh b/ci/dash/build_src.sh
index 3ebdc910dea2..ad1201e4599d 100755
--- a/ci/dash/build_src.sh
+++ b/ci/dash/build_src.sh
@@ -27,7 +27,7 @@ if [ "$CHECK_DOC" = 1 ]; then
     test/lint/all-lint.py
 fi
 
-ccache --zero-stats --max-size="$CCACHE_SIZE"
+ccache --zero-stats
 
 if [ -n "$CONFIG_SHELL" ]; then
   export CONFIG_SHELL="$CONFIG_SHELL"
diff --git a/ci/test/00_setup_env.sh b/ci/test/00_setup_env.sh
index d4840e9ebfd8..9ff3c333754e 100755
--- a/ci/test/00_setup_env.sh
+++ b/ci/test/00_setup_env.sh
@@ -55,7 +55,7 @@ export BOOST_TEST_RANDOM=${BOOST_TEST_RANDOM:-1}
 export DEBIAN_FRONTEND=noninteractive
 export HOST_CACHE_DIR=${HOST_CACHE_DIR:-$BASE_ROOT_DIR/ci-cache-$BUILD_TARGET}
 export CACHE_DIR=${CACHE_DIR:-$HOST_CACHE_DIR}
-export CCACHE_SIZE=${CCACHE_SIZE:-100M}
+export CCACHE_MAXSIZE=${CCACHE_MAXSIZE:-100M}
 export CCACHE_TEMPDIR=${CCACHE_TEMPDIR:-/tmp/.ccache-temp}
 export CCACHE_COMPRESS=${CCACHE_COMPRESS:-1}
 # The cache dir.
diff --git a/ci/test/00_setup_env_mac_native_x86_64.sh b/ci/test/00_setup_env_mac_native_x86_64.sh
index 0ac2d62eb6c5..252b95c2178f 100755
--- a/ci/test/00_setup_env_mac_native_x86_64.sh
+++ b/ci/test/00_setup_env_mac_native_x86_64.sh
@@ -14,6 +14,6 @@ export BITCOIN_CONFIG="--with-gui --enable-reduce-exports --disable-miner --with
 export CI_OS_NAME="macos"
 export NO_DEPENDS=1
 export OSX_SDK=""
-export CCACHE_SIZE=300M
+export CCACHE_MAXSIZE=300M
 
 export RUN_SECURITY_TESTS="true"
diff --git a/ci/test/00_setup_env_native_fuzz.sh b/ci/test/00_setup_env_native_fuzz.sh
index 18929cc2b2f0..ccb00222e902 100755
--- a/ci/test/00_setup_env_native_fuzz.sh
+++ b/ci/test/00_setup_env_native_fuzz.sh
@@ -16,3 +16,4 @@ export RUN_FUNCTIONAL_TESTS=false
 export RUN_FUZZ_TESTS=true
 export GOAL="install"
 export BITCOIN_CONFIG="--enable-zmq --disable-ccache --enable-fuzz --with-sanitizers=fuzzer,address,undefined,integer CC='clang-18 -ftrivial-auto-var-init=pattern' CXX='clang++-18 -ftrivial-auto-var-init=pattern' --with-boost-process"
+export CCACHE_MAXSIZE=200M
diff --git a/ci/test/00_setup_env_native_fuzz_with_valgrind.sh b/ci/test/00_setup_env_native_fuzz_with_valgrind.sh
index 1b5728feb84c..d1a553360738 100755
--- a/ci/test/00_setup_env_native_fuzz_with_valgrind.sh
+++ b/ci/test/00_setup_env_native_fuzz_with_valgrind.sh
@@ -16,4 +16,4 @@ export FUZZ_TESTS_CONFIG="--valgrind"
 export GOAL="install"
 # Temporarily pin dwarf 4, until valgrind can understand clang's dwarf 5
 export BITCOIN_CONFIG="--enable-fuzz --with-sanitizers=fuzzer CC=clang-18 CXX=clang++-18 CFLAGS='-gdwarf-4' CXXFLAGS='-gdwarf-4'"
-export CCACHE_SIZE=200M
+export CCACHE_MAXSIZE=200M