diff --git a/filecheck/FileCheck.py b/filecheck/FileCheck.py
index 6c5bcd0..d7ca42d 100755
--- a/filecheck/FileCheck.py
+++ b/filecheck/FileCheck.py
@@ -283,7 +283,7 @@ def exit_handler(code):
                 line = canonicalize_whitespace(line)
 
             # CHECK and CHECK-NEXT
-            strict_whitespace_match = "" if args.strict_whitespace and args.match_full_lines else " *"
+            strict_whitespace_match = "" if strict_mode else " *"
 
             check_regex = "{}({}):{}(.*)".format(before_prefix, check_prefix, strict_whitespace_match)
             check_match = re.search(check_regex, line)
@@ -296,7 +296,7 @@ def exit_handler(code):
             if check_match:
                 check_keyword = check_match.group(2)
                 check_expression = check_match.group(3)
-                if not (args.strict_whitespace and args.match_full_lines):
+                if not strict_mode:
                     check_expression = check_expression.strip(' ')
 
                 match_type = MatchType.SUBSTRING
@@ -306,6 +306,11 @@ def exit_handler(code):
                     regex_line = re.sub(r"\{\{(.*?)\}\}", r"\1", regex_line)
                     match_type = MatchType.REGEX
                     check_expression = regex_line
+                    if strict_mode:
+                        if check_expression[0] != "^":
+                            check_expression = "^" + check_expression
+                        if check_expression[-1] != "$":
+                            check_expression = check_expression + "$"
 
                 check = Check(check_type=check_type,
                               match_type=match_type,
@@ -325,7 +330,7 @@ def exit_handler(code):
 
                 check_keyword = check_match.group(2)
                 check_expression = check_match.group(3)
-                if not (args.strict_whitespace and args.match_full_lines):
+                if not strict_mode:
                     check_expression = check_expression.strip(' ')
 
                 if re.search(r"\{\{.*\}\}", check_expression):
diff --git a/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/filecheck.check b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/filecheck.check
new file mode 100644
index 0000000..7766435
--- /dev/null
+++ b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/filecheck.check
@@ -0,0 +1 @@
+CHECK:Substring2{{.*}}Substring3
diff --git a/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/filecheck.input b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/filecheck.input
new file mode 100644
index 0000000..ebd7468
--- /dev/null
+++ b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/filecheck.input
@@ -0,0 +1 @@
+Substring1 Substring2 Substring3
\ No newline at end of file
diff --git a/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/sample.itest b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/sample.itest
new file mode 100644
index 0000000..3d379eb
--- /dev/null
+++ b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/03_negative_regex_substring_begin/sample.itest
@@ -0,0 +1,7 @@
+RUN: %cat "%S/filecheck.input" | %expect_exit 1 %FILECHECK_EXEC "%S/filecheck.check" --match-full-lines --strict-whitespace
+CHECK:{{.*}}filecheck.check:1:7: error: CHECK: expected string not found in input
+CHECK:CHECK:Substring2{{.*}}Substring3
+CHECK:      ^
+CHECK:<stdin>:1:1: note: scanning from here
+CHECK:Substring1 Substring2 Substring3
+CHECK:^
diff --git a/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/filecheck.check b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/filecheck.check
new file mode 100644
index 0000000..e54fd97
--- /dev/null
+++ b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/filecheck.check
@@ -0,0 +1 @@
+CHECK:Substring1{{.*}}Substring2
diff --git a/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/filecheck.input b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/filecheck.input
new file mode 100644
index 0000000..ebd7468
--- /dev/null
+++ b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/filecheck.input
@@ -0,0 +1 @@
+Substring1 Substring2 Substring3
\ No newline at end of file
diff --git a/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/sample.itest b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/sample.itest
new file mode 100644
index 0000000..11a764a
--- /dev/null
+++ b/tests/integration/tests/options/--match-full-lines/CHECK/02_when_strict_whitespace_is_also_specified/04_negative_regex_substring_end/sample.itest
@@ -0,0 +1,7 @@
+RUN: %cat "%S/filecheck.input" | %expect_exit 1 %FILECHECK_EXEC "%S/filecheck.check" --match-full-lines --strict-whitespace
+CHECK:{{.*}}filecheck.check:1:7: error: CHECK: expected string not found in input
+CHECK:CHECK:Substring1{{.*}}Substring2
+CHECK:      ^
+CHECK:<stdin>:1:1: note: scanning from here
+CHECK:Substring1 Substring2 Substring3
+CHECK:^