diff --git a/completions/_mock b/completions/_mock
index 480c4007a9e..c956cb726b0 100644
--- a/completions/_mock
+++ b/completions/_mock
@@ -45,7 +45,7 @@ _comp_cmd_mock()
             # This would actually depend on what the target root
             # can be used to build for...
             _comp_compgen_split -- "$(command rpm --showrc | command sed -ne \
-                's/^\s*compatible\s\s*archs\s*:\s*\(.*\)/\1/i p')"
+                's/^[[:space:]]*compatible[[:space:]]\{1,\}archs[[:space:]]*:[[:space:]]*\(.*\)/\1/i p')"
             return
             ;;
         --enable-plugin | --disable-plugin)
diff --git a/completions/_yum b/completions/_yum
index 9933fd80ed2..8879c81778a 100644
--- a/completions/_yum
+++ b/completions/_yum
@@ -25,7 +25,7 @@ _comp_cmd_yum__compgen_repolist()
     # Drop first ("repo id      repo name") and last ("repolist: ...") rows
     _comp_compgen_split -- "$(
         yum --noplugins -C repolist "$1" 2>/dev/null |
-            command sed -ne '/^repo\s\s*id/d' -e '/^repolist:/d' \
+            command sed -ne '/^repo[[:space:]]\{1,\}id/d' -e '/^repolist:/d' \
                 -e 's/[[:space:]].*//p'
     )"
 }
diff --git a/completions/chronyc b/completions/chronyc
index 7c1a74e1b41..15a784b2279 100644
--- a/completions/chronyc
+++ b/completions/chronyc
@@ -4,7 +4,7 @@ _comp_cmd_chronyc__command_args()
 {
     local -a args
     _comp_split args "$("$1" help 2>/dev/null |
-        _comp_awk '/^'"$prev"'\s[^ []/ { gsub("\\|", " ", $2); print $2 }')"
+        _comp_awk '/^'"$prev"'[ \t][^ []/ { gsub("\\|", " ", $2); print $2 }')"
     case $args in
         \<address\>) _comp_compgen_known_hosts -- "$cur" ;;
         \<*) ;;
diff --git a/completions/puppet b/completions/puppet
index a6f5d5985e7..3a8f5859008 100644
--- a/completions/puppet
+++ b/completions/puppet
@@ -24,7 +24,7 @@ _comp_cmd_puppet__certs()
     if [[ $1 == --all ]]; then
         cert_list=$(
             $puppetca --list --all |
-                command sed -e 's/^[+-]\{0,1\}\s*\(\S\{1,\}\)\s\{1,\}.*$/\1/'
+                command sed -e 's/^[+-]\{0,1\}[[:space:]]*\([^[:space:]]\{1,\}\)[[:space:]]\{1,\}.*$/\1/'
         )
     else
         cert_list=$("$puppetca" --list)
@@ -35,7 +35,7 @@ _comp_cmd_puppet__certs()
 _comp_cmd_puppet__types()
 {
     puppet_types=$(
-        puppet describe --list | command sed -e 's/^\(\S\{1,\}\).*$/\1/'
+        puppet describe --list | command sed -e 's/^\([^[:space:]]\{1,\}\).*$/\1/'
     )
     _comp_compgen -a -- -W "$puppet_types"
 }
@@ -47,7 +47,7 @@ _comp_cmd_puppet__references()
         puppetdoc=puppetdoc
 
     puppet_doc_list=$(
-        $puppetdoc --list | command sed -e 's/^\(\S\{1,\}\).*$/\1/'
+        $puppetdoc --list | command sed -e 's/^\([^[:space:]]\{1,\}\).*$/\1/'
     )
     _comp_compgen -a -- -W "$puppet_doc_list"
 }
diff --git a/completions/rpm b/completions/rpm
index c9e95bbae72..fdb65ece2a1 100644
--- a/completions/rpm
+++ b/completions/rpm
@@ -45,7 +45,7 @@ _comp_cmd_rpm__macros()
 _comp_cmd_rpm__buildarchs()
 {
     _comp_compgen_split -- "$("${1:-rpm}" --showrc | command sed -ne \
-        's/^\s*compatible\s\s*build\s\s*archs\s*:\s*\(.*\)/\1/ p')"
+        's/^[[:space:]]*compatible[[:space:]]\{1,\}build[[:space:]]\{1,\}archs[[:space:]]*:[[:space:]]*\(.*\)/\1/ p')"
 }
 
 # shellcheck disable=SC2120