diff --git a/cmd/geth/logging_test.go b/cmd/geth/logging_test.go
index b5ce03f4b8..f426b138bb 100644
--- a/cmd/geth/logging_test.go
+++ b/cmd/geth/logging_test.go
@@ -73,6 +73,7 @@ func testConsoleLogging(t *testing.T, format string, tStart, tEnd int) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer readFile.Close()
 	wantLines := split(readFile)
 	haveLines := split(bytes.NewBuffer(haveB))
 	for i, want := range wantLines {
@@ -109,6 +110,7 @@ func TestJsonLogging(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer readFile.Close()
 	wantLines := split(readFile)
 	haveLines := split(bytes.NewBuffer(haveB))
 	for i, wantLine := range wantLines {
diff --git a/cmd/utils/history_test.go b/cmd/utils/history_test.go
index b6703c59ed..520a0d84cd 100644
--- a/cmd/utils/history_test.go
+++ b/cmd/utils/history_test.go
@@ -113,6 +113,7 @@ func TestHistoryImportAndExport(t *testing.T) {
 			if err != nil {
 				t.Fatalf("error opening era file: %v", err)
 			}
+			defer f.Close()
 			var (
 				h   = sha256.New()
 				buf = bytes.NewBuffer(nil)
diff --git a/core/mkalloc.go b/core/mkalloc.go
index 201c2fe7de..cc4955f038 100644
--- a/core/mkalloc.go
+++ b/core/mkalloc.go
@@ -101,6 +101,7 @@ func main() {
 	if err != nil {
 		panic(err)
 	}
+	defer file.Close()
 	if err := json.NewDecoder(file).Decode(g); err != nil {
 		panic(err)
 	}