diff --git a/staging/src/k8s.io/apiextensions-apiserver/hack/update-codegen.sh b/staging/src/k8s.io/apiextensions-apiserver/hack/update-codegen.sh
index 8261e98d56a..f5dc31758ca 100755
--- a/staging/src/k8s.io/apiextensions-apiserver/hack/update-codegen.sh
+++ b/staging/src/k8s.io/apiextensions-apiserver/hack/update-codegen.sh
@@ -23,7 +23,7 @@ CODEGEN_PKG=${CODEGEN_PKG:-$(cd "${SCRIPT_ROOT}"; ls -d -1 ./vendor/k8s.io/code-
 
 CLIENTSET_NAME_VERSIONED=clientset \
 CLIENTSET_PKG_NAME=clientset \
-"${CODEGEN_PKG}/generate-groups.sh" "deepcopy,client,lister,informer" \
+"${CODEGEN_PKG}/generate-groups.sh" "deepcopy,defaulter,client,lister,informer" \
   k8s.io/apiextensions-apiserver/pkg/client \
   k8s.io/apiextensions-apiserver/pkg/apis \
   "apiextensions:v1beta1,v1" \
diff --git a/staging/src/k8s.io/code-generator/generate-groups.sh b/staging/src/k8s.io/code-generator/generate-groups.sh
index 8e993294c63..63fb68bb6be 100755
--- a/staging/src/k8s.io/code-generator/generate-groups.sh
+++ b/staging/src/k8s.io/code-generator/generate-groups.sh
@@ -25,7 +25,7 @@ if [ "$#" -lt 4 ] || [ "${1}" == "--help" ]; then
   cat <<EOF
 Usage: $(basename "$0") <generators> <output-package> <apis-package> <groups-versions> ...
 
-  <generators>        the generators comma separated to run (deepcopy,applyconfiguration,client,lister,informer) or "all".
+  <generators>        the generators comma separated to run (deepcopy, defaulter,applyconfiguration,client,lister,informer) or "all".
   <output-package>    the output package name (e.g. github.com/example/project/pkg/generated).
   <apis-package>      the external types dir (e.g. github.com/example/api or github.com/example/project/pkg/apis).
   <groups-versions>   the groups and their versions in the format "groupA:v1,v2 groupB:v1 groupC:v2", relative
@@ -50,7 +50,7 @@ shift 4
   # To support running this script from anywhere, first cd into this directory,
   # and then install with forced module mode on and fully qualified name.
   cd "$(dirname "${0}")"
-  GO111MODULE=on go install k8s.io/code-generator/cmd/{applyconfiguration-gen,client-gen,lister-gen,informer-gen,deepcopy-gen}
+  GO111MODULE=on go install k8s.io/code-generator/cmd/{applyconfiguration-gen,client-gen,lister-gen,informer-gen,deepcopy-gen,defaulter-gen}
 )
 # Go installs the above commands to get installed in $GOBIN if defined, and $GOPATH/bin otherwise:
 GOBIN="$(go env GOBIN)"
@@ -77,6 +77,14 @@ if [ "${GENS}" = "all" ] || grep -qw "deepcopy" <<<"${GENS}"; then
       "$@"
 fi
 
+if [ "${GENS}" = "all" ] || grep -qw "defaulter" <<<"${GENS}"; then
+  echo "Generating defaulters"
+  "${gobin}/defaulter-gen"  \
+      --input-dirs "$(codegen::join , "${FQ_APIS[@]}")" \
+      -O zz_generated.defaults \
+      "$@"
+fi
+
 if [ "${GENS}" = "all" ] || grep -qw "applyconfiguration" <<<"${GENS}"; then
   echo "Generating apply configuration for ${GROUPS_WITH_VERSIONS} at ${OUTPUT_PKG}/${APPLYCONFIGURATION_PKG_NAME:-applyconfiguration}"
   "${gobin}/applyconfiguration-gen" \
diff --git a/staging/src/k8s.io/code-generator/hack/update-codegen.sh b/staging/src/k8s.io/code-generator/hack/update-codegen.sh
index ff4dd288aa2..27cfd431b33 100755
--- a/staging/src/k8s.io/code-generator/hack/update-codegen.sh
+++ b/staging/src/k8s.io/code-generator/hack/update-codegen.sh
@@ -31,19 +31,19 @@ SCRIPT_ROOT=$(dirname "${BASH_SOURCE[0]}")/..
   "example:v1 example2:v1 example3.io:v1" \
   --output-base "$(dirname "${BASH_SOURCE[0]}")/../../.." \
   --go-header-file "${SCRIPT_ROOT}/hack/boilerplate.go.txt"
-"${SCRIPT_ROOT}/generate-groups.sh" "applyconfiguration,client,deepcopy,informer,lister" \
+"${SCRIPT_ROOT}/generate-groups.sh" "applyconfiguration,client,deepcopy,defaulter,informer,lister" \
   k8s.io/code-generator/examples/crd \
   k8s.io/code-generator/examples/crd/apis \
   "example:v1 example2:v1" \
   --output-base "$(dirname "${BASH_SOURCE[0]}")/../../.." \
   --go-header-file "${SCRIPT_ROOT}/hack/boilerplate.go.txt"
-"${SCRIPT_ROOT}/generate-groups.sh" "applyconfiguration,client,deepcopy,informer,lister" \
+"${SCRIPT_ROOT}/generate-groups.sh" "applyconfiguration,client,deepcopy,defaulter,informer,lister" \
   k8s.io/code-generator/examples/MixedCase \
   k8s.io/code-generator/examples/MixedCase/apis \
   "example:v1" \
   --output-base "$(dirname "${BASH_SOURCE[0]}")/../../.." \
   --go-header-file "${SCRIPT_ROOT}/hack/boilerplate.go.txt"
-"${SCRIPT_ROOT}/generate-groups.sh" "applyconfiguration,client,deepcopy,informer,lister" \
+"${SCRIPT_ROOT}/generate-groups.sh" "applyconfiguration,client,deepcopy,defaulter,informer,lister" \
   k8s.io/code-generator/examples/HyphenGroup \
   k8s.io/code-generator/examples/HyphenGroup/apis \
   "example:v1" \
diff --git a/staging/src/k8s.io/kube-aggregator/hack/update-codegen.sh b/staging/src/k8s.io/kube-aggregator/hack/update-codegen.sh
index f85abd44ccc..ef04f9bd650 100755
--- a/staging/src/k8s.io/kube-aggregator/hack/update-codegen.sh
+++ b/staging/src/k8s.io/kube-aggregator/hack/update-codegen.sh
@@ -23,7 +23,7 @@ CODEGEN_PKG=${CODEGEN_PKG:-$(cd "${SCRIPT_ROOT}"; ls -d -1 ./vendor/k8s.io/code-
 
 CLIENTSET_NAME_VERSIONED=clientset \
 CLIENTSET_PKG_NAME=clientset_generated \
-"${CODEGEN_PKG}/generate-groups.sh" "deepcopy,client,lister,informer" \
+"${CODEGEN_PKG}/generate-groups.sh" "deepcopy,defaulter,client,lister,informer" \
   k8s.io/kube-aggregator/pkg/client \
   k8s.io/kube-aggregator/pkg/apis \
   "apiregistration:v1beta1,v1" \