diff --git a/builtin/providers/azurerm/tags_test.go b/builtin/providers/azurerm/tags_test.go
new file mode 100644
index 000000000..fb75c04f0
--- /dev/null
+++ b/builtin/providers/azurerm/tags_test.go
@@ -0,0 +1,97 @@
+package azurerm
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+)
+
+func TestValidateMaximumNumberOfARMTags(t *testing.T) {
+	tagsMap := make(map[string]interface{})
+	for i := 0; i < 16; i++ {
+		tagsMap[fmt.Sprintf("key%d", i)] = fmt.Sprintf("value%d", i)
+	}
+
+	_, es := validateAzureRMTags(tagsMap, "tags")
+
+	if len(es) != 1 {
+		t.Fatal("Expected one validation error for too many tags")
+	}
+
+	if !strings.Contains(es[0].Error(), "a maximum of 15 tags") {
+		t.Fatal("Wrong validation error message for too many tags")
+	}
+}
+
+func TestValidateARMTagMaxKeyLength(t *testing.T) {
+	tooLongKey := strings.Repeat("long", 128) + "a"
+	tagsMap := make(map[string]interface{})
+	tagsMap[tooLongKey] = "value"
+
+	_, es := validateAzureRMTags(tagsMap, "tags")
+	if len(es) != 1 {
+		t.Fatal("Expected one validation error for a key which is > 512 chars")
+	}
+
+	if !strings.Contains(es[0].Error(), "maximum length for a tag key") {
+		t.Fatal("Wrong validation error message maximum tag key length")
+	}
+
+	if !strings.Contains(es[0].Error(), tooLongKey) {
+		t.Fatal("Expected validated error to contain the key name")
+	}
+
+	if !strings.Contains(es[0].Error(), "513") {
+		t.Fatal("Expected the length in the validation error for tag key")
+	}
+}
+
+func TestValidateARMTagMaxValueLength(t *testing.T) {
+	tagsMap := make(map[string]interface{})
+	tagsMap["toolong"] = strings.Repeat("long", 64) + "a"
+
+	_, es := validateAzureRMTags(tagsMap, "tags")
+	if len(es) != 1 {
+		t.Fatal("Expected one validation error for a value which is > 256 chars")
+	}
+
+	if !strings.Contains(es[0].Error(), "maximum length for a tag value") {
+		t.Fatal("Wrong validation error message for maximum tag value length")
+	}
+
+	if !strings.Contains(es[0].Error(), "toolong") {
+		t.Fatal("Expected validated error to contain the key name")
+	}
+
+	if !strings.Contains(es[0].Error(), "257") {
+		t.Fatal("Expected the length in the validation error for value")
+	}
+}
+
+func TestExpandARMTags(t *testing.T) {
+	testData := make(map[string]interface{})
+	testData["key1"] = "value1"
+	testData["key2"] = 21
+	testData["key3"] = "value3"
+
+	tempExpanded := expandTags(testData)
+	expanded := *tempExpanded
+
+	if len(expanded) != 3 {
+		t.Fatalf("Expected 3 results in expanded tag map, got %d", len(expanded))
+	}
+
+	for k, v := range testData {
+		var strVal string
+		switch v.(type) {
+		case string:
+			strVal = v.(string)
+		case int:
+			strVal = fmt.Sprintf("%d", v.(int))
+		}
+
+		if *expanded[k] != strVal {
+			t.Fatalf("Expanded value %q incorrect: expected %q, got %q", k, strVal, expanded[k])
+		}
+	}
+}