diff --git a/internal/actions/mocks/container.go b/internal/actions/mocks/container.go
index e830587..86f99b5 100644
--- a/internal/actions/mocks/container.go
+++ b/internal/actions/mocks/container.go
@@ -79,6 +79,13 @@ func CreateMockContainerWithDigest(id string, name string, image string, created
 	return c
 }
 
+// CreateMockContainerWithDigest should only be used for testing
+func CreateMockContainerWithImageCreatedTime(id string, name string, image string, created time.Time, imageCreated time.Time) wt.Container {
+	c := CreateMockContainer(id, name, image, created)
+	c.ImageInfo().Created = imageCreated.UTC().Format(time.RFC3339)
+	return c
+}
+
 // CreateMockContainerWithConfig creates a container substitute valid for testing
 func CreateMockContainerWithConfig(id string, name string, image string, running bool, restarting bool, created time.Time, config *dockerContainer.Config) wt.Container {
 	content := types.ContainerJSON{
diff --git a/internal/actions/update_test.go b/internal/actions/update_test.go
index 9209dcd..e3a5df9 100644
--- a/internal/actions/update_test.go
+++ b/internal/actions/update_test.go
@@ -65,6 +65,35 @@ func getLinkedTestData(withImageInfo bool) *TestData {
 	}
 }
 
+func getMixedAgeTestData(keepContainer string) *TestData {
+	return &TestData{
+		NameOfContainerToKeep: keepContainer,
+		Containers: []types.Container{
+			// new container with 5 day old image
+			CreateMockContainerWithImageCreatedTime(
+				"test-container-01",
+				"test-container-01",
+				"fake-image-01:latest",
+				time.Now(),
+				time.Now().AddDate(0, 0, -5)),
+			// new container with 1 day old image
+			CreateMockContainerWithImageCreatedTime(
+				"test-container-02",
+				"test-container-02",
+				"fake-image-02:latest",
+				time.Now(),
+				time.Now().AddDate(0, 0, -1)),
+			// new container with 1 hour old image
+			CreateMockContainerWithImageCreatedTime(
+				"test-container-03",
+				"test-container-03",
+				"fake-image-03:latest",
+				time.Now(),
+				time.Now().Add(-1*time.Hour)),
+		},
+	}
+}
+
 var _ = Describe("the update action", func() {
 	When("watchtower has been instructed to clean up", func() {
 		When("there are multiple containers using the same image", func() {
@@ -258,6 +287,37 @@ var _ = Describe("the update action", func() {
 		})
 	})
 
+	When("watchtower has been instructed to defer updates by some number of days", func() {
+		It("should only update the 1 container with image at least 2 days old when DeferDays is 2", func() {
+			client := CreateMockClient(getMixedAgeTestData(""), false, false)
+			report, err := actions.Update(client, types.UpdateParams{DeferDays: 2})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(report.Updated()).To(HaveLen(1))
+			Expect(report.Deferred()).To(HaveLen(2))
+		})
+		It("should only update the 2 containers with image at least 1 day old when DeferDays is 1", func() {
+			client := CreateMockClient(getMixedAgeTestData(""), false, false)
+			report, err := actions.Update(client, types.UpdateParams{DeferDays: 1})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(report.Updated()).To(HaveLen(2))
+			Expect(report.Deferred()).To(HaveLen(1))
+		})
+		It("should update all containers when DeferDays is 0", func() {
+			client := CreateMockClient(getMixedAgeTestData(""), false, false)
+			report, err := actions.Update(client, types.UpdateParams{DeferDays: 0})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(report.Updated()).To(HaveLen(3))
+			Expect(report.Deferred()).To(HaveLen(0))
+		})
+		It("should update all containers when DeferDays is not specified", func() {
+			client := CreateMockClient(getMixedAgeTestData(""), false, false)
+			report, err := actions.Update(client, types.UpdateParams{})
+			Expect(err).NotTo(HaveOccurred())
+			Expect(report.Updated()).To(HaveLen(3))
+			Expect(report.Deferred()).To(HaveLen(0))
+		})
+	})
+
 	When("watchtower has been instructed to run lifecycle hooks", func() {
 
 		When("pre-update script returns 1", func() {